U.S. patent application number 17/684138 was filed with the patent office on 2022-08-18 for wakeup signaling resource occasions.
The applicant listed for this patent is QUALCOMM Incorporated. Invention is credited to Tao Luo, Wooseok Nam.
Application Number | 20220264453 17/684138 |
Document ID | / |
Family ID | 1000006305890 |
Filed Date | 2022-08-18 |
United States Patent
Application |
20220264453 |
Kind Code |
A1 |
Nam; Wooseok ; et
al. |
August 18, 2022 |
WAKEUP SIGNALING RESOURCE OCCASIONS
Abstract
Methods, systems, and devices for wireless communications are
described. Some wireless communications systems support user
equipment (UEs) achieving power savings by operating in a connected
discontinuous reception (C-DRX) mode. The systems may additionally
utilize wakeup signals for further power savings at a UE. For
example, a UE may be configured with a wakeup signal resource
configuration (e.g., a first search space configuration) for
monitoring for wakeup signals while operating in a low power mode.
This first search space configuration may be different from a
second search space configuration for the UE operating in an active
mode. When in a low power mode, the UE may monitor for wakeup
signals according to the wakeup signal resource configuration. If
the UE receives a wakeup signal in a wakeup signal resource defined
by the configuration, the UE may initiate a wakeup procedure and
transition to the active mode for data transmission and
reception.
Inventors: |
Nam; Wooseok; (San Diego,
CA) ; Luo; Tao; (San Diego, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QUALCOMM Incorporated |
San Diego |
CA |
US |
|
|
Family ID: |
1000006305890 |
Appl. No.: |
17/684138 |
Filed: |
March 1, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16592675 |
Oct 3, 2019 |
11297569 |
|
|
17684138 |
|
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62742227 |
Oct 5, 2018 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 72/1289 20130101;
H04W 52/0241 20130101; H04W 52/0216 20130101 |
International
Class: |
H04W 52/02 20060101
H04W052/02; H04W 72/12 20060101 H04W072/12 |
Claims
1. (canceled)
2. An apparatus for wireless communications at a user equipment
(UE), comprising: a processor; memory coupled with the processor;
and instructions stored in the memory and executable by the
processor to cause the apparatus to: receive, using a first
receiver based at least in part on the UE operating in an active
mode, control signaling indicating a configuration comprising a
plurality of wakeup signal resources for the UE; and monitor, using
a second receiver associated with a wakeup subsystem of the UE
based at least in part on the UE operating outside the active mode,
for a wakeup signal in a wakeup signal resource of the plurality of
wakeup signal resources based at least in part on the
configuration, wherein the second receiver is different from the
first receiver.
3. The apparatus of claim 2, wherein the instructions are further
executable by the processor to cause the apparatus to: receive,
using the second receiver associated with the wakeup subsystem of
the UE, the wakeup signal based at least in part on the monitoring;
and enter the active mode based at least in part on the received
wakeup signal.
4. The apparatus of claim 3, wherein the wakeup signal comprises a
scrambling sequence, and the instructions are further executable by
the processor to cause the apparatus to: decode the wakeup signal
based at least in part on the scrambling sequence, wherein the
entering the active mode is further based at least in part on the
decoding the wakeup signal.
5. The apparatus of claim 2, wherein the instructions are further
executable by the processor to cause the apparatus to: enter a low
power mode outside the active mode; and activate the second
receiver associated with the wakeup subsystem of the UE based at
least in part on the entering the low power mode, wherein the
monitoring uses the second receiver associated with the wakeup
subsystem of the UE based at least in part on the activating the
second receiver.
6. The apparatus of claim 2, wherein: the control signaling
configures the UE to monitor for a plurality of reference signals
for initiating a wakeup procedure; and the wakeup signal comprises
a reference signal of the plurality of reference signals.
7. The apparatus of claim 6, wherein the instructions to monitor
are executable by the processor to cause the apparatus to: monitor
for the plurality of reference signals for initiating the wakeup
procedure according to the configuration based at least in part on
the UE operating outside the active mode; and refrain from
monitoring for the plurality of reference signals for initiating
the wakeup procedure according to the configuration based at least
in part on the UE operating in the active mode.
8. The apparatus of claim 2, wherein the second receiver associated
with the wakeup subsystem of the UE operates using a lower power
than the first receiver.
9. The apparatus of claim 2, wherein the instructions are further
executable by the processor to cause the apparatus to: operate in a
discontinuous reception (DRX) mode, wherein the active mode
corresponds to an active duration for the DRX mode.
10. The apparatus of claim 2, wherein the control signaling
configures the UE with a time resource, a frequency resource, or
both for the wakeup signal resource of the plurality of wakeup
signal resources.
11. The apparatus of claim 2, wherein the instructions are further
executable by the processor to cause the apparatus to: fail to
receive, using the second receiver associated with the wakeup
subsystem of the UE, the wakeup signal based at least in part on
the monitoring; and refrain from entering the active mode based at
least in part on the failing to receive the wakeup signal.
12. A method for wireless communications at a user equipment (UE),
comprising: receiving, using a first receiver based at least in
part on the UE operating in an active mode, control signaling
indicating a configuration comprising a plurality of wakeup signal
resources for the UE; and monitoring, using a second receiver
associated with a wakeup subsystem of the UE based at least in part
on the UE operating outside the active mode, for a wakeup signal in
a wakeup signal resource of the plurality of wakeup signal
resources based at least in part on the configuration, wherein the
second receiver is different from the first receiver.
13. The method of claim 12, further comprising: receiving, using
the second receiver associated with the wakeup subsystem of the UE,
the wakeup signal based at least in part on the monitoring; and
entering the active mode based at least in part on the received
wakeup signal.
14. The method of claim 13, wherein the wakeup signal comprises a
scrambling sequence, the method further comprising: decoding the
wakeup signal based at least in part on the scrambling sequence,
wherein the entering the active mode is further based at least in
part on the decoding the wakeup signal.
15. The method of claim 12, further comprising: entering a low
power mode outside the active mode; and activating the second
receiver associated with the wakeup subsystem of the UE based at
least in part on the entering the low power mode, wherein the
monitoring uses the second receiver associated with the wakeup
subsystem of the UE based at least in part on the activating the
second receiver.
16. The method of claim 12, wherein: the control signaling
configures the UE to monitor for a plurality of reference signals
for initiating a wakeup procedure; and the wakeup signal comprises
a reference signal of the plurality of reference signals.
17. The method of claim 16, wherein the monitoring comprises:
monitoring for the plurality of reference signals for initiating
the wakeup procedure according to the configuration based at least
in part on the UE operating outside the active mode; and refraining
from monitoring for the plurality of reference signals for
initiating the wakeup procedure according to the configuration
based at least in part on the UE operating in the active mode.
18. The method of claim 12, wherein the second receiver associated
with the wakeup subsystem of the UE operates using a lower power
than the first receiver.
19. The method of claim 12, further comprising: operating in a
discontinuous reception (DRX) mode, wherein the active mode
corresponds to an active duration for the DRX mode.
20. The method of claim 12, wherein the control signaling
configures the UE with a time resource, a frequency resource, or
both for the wakeup signal resource of the plurality of wakeup
signal resources.
21. An apparatus for wireless communications at a user equipment
(UE), comprising: means for receiving, using a first receiver based
at least in part on the UE operating in an active mode, control
signaling indicating a configuration comprising a plurality of
wakeup signal resources for the UE; and means for monitoring, using
a second receiver associated with a wakeup subsystem of the UE
based at least in part on the UE operating outside the active mode,
for a wakeup signal in a wakeup signal resource of the plurality of
wakeup signal resources based at least in part on the
configuration, wherein the second receiver is different from the
first receiver.
Description
CROSS REFERENCE
[0001] The present application for patent is a Continuation of U.S.
patent application Ser. No. 16/592,675 by NAM et al., entitled
"WAKEUP SIGNALING RESOURCE OCCASIONS" filed Oct. 3, 2019, which
claims the benefit of U.S. Provisional Patent Application No.
62/742,227 by NAM et al., entitled "WAKEUP SIGNALING RESOURCE
OCCASIONS," filed Oct. 5, 2018, assigned to the assignee hereof,
and expressly incorporated herein.
BACKGROUND
[0002] The following relates generally to wireless communications,
and more specifically to wakeup signaling resource occasions.
[0003] Wireless communications systems are widely deployed to
provide various types of communication content such as voice,
video, packet data, messaging, broadcast, and so on. These systems
may be capable of supporting communication with multiple users by
sharing the available system resources (e.g., time, frequency, and
power). Examples of such multiple-access systems include fourth
generation (4G) systems such as Long Term Evolution (LTE) systems,
LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth
generation (5G) systems which may be referred to as New Radio (NR)
systems. These systems may employ technologies such as code
division multiple access (CDMA), time division multiple access
(TDMA), frequency division multiple access (FDMA), orthogonal
frequency division multiple access (OFDMA), or discrete Fourier
transform-spread-OFDM (DFT-S-OFDM). A wireless multiple-access
communications system may include a number of base stations or
network access nodes, each simultaneously supporting communication
for multiple communication devices, which may be otherwise known as
user equipment (UE).
[0004] Some wireless communications systems may support UEs
operating in a discontinuous reception (DRX) mode (e.g., a
connected DRX (C-DRX) mode), where a UE may transition between an
active state for data transmission and reception and a sleep state
for power conservation. The UE may determine if data is available
by monitoring a control channel, such as a physical downlink
control channel (PDCCH). The PDCCH may carry or otherwise convey an
indication that a base station has data ready to transmit to the
UE. In some cases, to reduce the frequency of the control channel
monitoring, the UE may monitor for a wakeup signal using a low
complexity receiver and may skip a control channel monitoring
opportunity if no wakeup signal is received. However, in systems
with a large number of UEs, UEs may detect wakeup signals intended
for other UEs and may perform a wakeup procedure despite a base
station not scheduling the UEs for any data communications. These
UEs that wake up unnecessarily may experience reduced power savings
due to the incorrectly identified wakeup signals.
SUMMARY
[0005] The described techniques relate to improved methods,
systems, devices, and apparatuses that support wakeup signaling
resource occasions. Generally, the described techniques provide for
improved power savings at user equipment (UEs). Some wireless
communications systems support UEs achieving power savings by
operating in a connected discontinuous reception (C-DRX) mode. The
systems may additionally utilize wakeup signals for further power
savings at a UE. For example, a UE may be configured with a
UE-specific or UE group-specific wakeup signal resource
configuration (e.g., a first search space set configuration). This
wakeup signal resource configuration may indicate a number of
resource configuration parameters, such as time resource
information, frequency resource information, decoding parameter
information, beam sweeping information, or some combination of
these parameters. When in a low power mode, the UE may monitor for
wakeup signals according to the wakeup signal resource
configuration and the corresponding parameters. If the UE receives
a wakeup signal in a wakeup signal resource defined by the
configuration, the UE may determine that the wakeup signal is
intended for the UE (e.g., based on the configuration parameters).
According to this determination, the UE may initiate a wakeup
procedure and transition to an active mode for data transmission
and reception. While in the active mode, the UE may monitor for
downlink control information (DCI) messages according to a second
search space set configuration different from the first search
space set configuration. Additionally, while in the low power mode,
if the UE detects a wakeup signal that does not correspond to the
wakeup signal resource configuration for the UE, the UE may
determine that the wakeup signal is intended for a different UE and
may not wake up. In this way, UEs may better differentiate between
wakeup signals transmitted by a base station, reducing the number
of unnecessary wakeup procedures performed by the UEs and,
correspondingly, improving the power savings at the UEs.
[0006] A method for wireless communication at a UE is described.
The method may include receiving a first search space configuration
for monitoring a downlink control channel while operating in a low
power mode of the UE, receiving a second search space configuration
for monitoring the downlink control channel while operating in an
active mode of the UE, where the second search space configuration
is different from the first search space configuration, and
monitoring the downlink control channel according to the first
search space configuration for a wakeup signal transmission based
on the UE operating in the low power mode.
[0007] An apparatus for wireless communication at a UE is
described. The apparatus may include a processor, memory coupled
with the processor, and instructions stored in the memory. The
instructions may be executable by the processor to cause the
apparatus to receive a first search space configuration for
monitoring a downlink control channel while operating in a low
power mode of the UE, receive a second search space configuration
for monitoring the downlink control channel while operating in an
active mode of the UE, where the second search space configuration
is different from the first search space configuration, and monitor
the downlink control channel according to the first search space
configuration for a wakeup signal transmission based on the UE
operating in the low power mode.
[0008] Another apparatus for wireless communication at a UE is
described. The apparatus may include means for receiving a first
search space configuration for monitoring a downlink control
channel while operating in a low power mode of the UE, receiving a
second search space configuration for monitoring the downlink
control channel while operating in an active mode of the UE, where
the second search space configuration is different from the first
search space configuration, and monitoring the downlink control
channel according to the first search space configuration for a
wakeup signal transmission based on the UE operating in the low
power mode.
[0009] A non-transitory computer-readable medium storing code for
wireless communication at a UE is described. The code may include
instructions executable by a processor to receive a first search
space configuration for monitoring a downlink control channel while
operating in a low power mode of the UE, receive a second search
space configuration for monitoring the downlink control channel
while operating in an active mode of the UE, where the second
search space configuration is different from the first search space
configuration, and monitor the downlink control channel according
to the first search space configuration for a wakeup signal
transmission based on the UE operating in the low power mode.
[0010] Some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein may further include
operations, features, means, or instructions for detecting a wakeup
signal for the UE based on monitoring the downlink control channel
according to the first search space configuration, initiating a
wakeup procedure based on detecting the wakeup signal, and
monitoring the downlink control channel subsequent to initiating
the wakeup procedure according to the second search space
configuration based on the UE operating in the active mode.
[0011] Some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein may further include
operations, features, means, or instructions for detecting a grant
from a serving base station based on monitoring the downlink
control channel according to the second search space configuration
and communicating with the serving base station based on the grant.
Some other examples of the method, apparatuses, and non-transitory
computer-readable medium described herein may further include
operations, features, means, or instructions for initiating a sleep
procedure based on determining that a grant has not been received
within a defined amount of time from monitoring the downlink
control channel according to the second search space configuration
and monitoring the downlink control channel subsequent to
initiating the sleep procedure according to the first search space
configuration based on the UE operating in the low power mode.
[0012] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the
downlink control channel may be monitored according to the first
search space configuration using a low power receiver based on the
UE operating in the low power mode and the downlink control channel
may be monitored according to the second search space configuration
using a standard receiver different from the low power receiver
based on the UE operating in the active mode.
[0013] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
search space configuration includes multiple control resource sets
(CORESETs) in a bandwidth part (BWP), multiple control channel
monitoring occasions within a transmission time interval (TTI), or
both.
[0014] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
search space configuration includes at least one resource
configuration parameter and the monitoring the downlink control
channel may be based on the at least one resource configuration
parameter.
[0015] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a starting
symbol within a TTI, and where monitoring the downlink control
channel further may include operations, features, means, or
instructions for monitoring the downlink control channel according
to the first search space configuration for the wakeup signal
transmission beginning at the starting symbol within the TTI. In
some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the at least one
resource configuration parameter indicates a number of symbols
within the TTI, and where monitoring the downlink control channel
further may include operations, features, means, or instructions
for monitoring the downlink control channel according to the first
search space configuration for the wakeup signal transmission
beginning within the TTI at the starting symbol and continuing for
the number of symbols.
[0016] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter may be a frequency
resource configuration parameter, a time resource configuration
parameter, or both, and where monitoring the downlink control
channel further may include operations, features, means, or
instructions for monitoring the downlink control channel according
to the first search space configuration for the wakeup signal
transmission based on the frequency resource configuration
parameter, the time resource configuration parameter, or both. In
some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the frequency resource
configuration parameter may be a CORESET configuration parameter,
the time resource configuration parameter indicates a control
channel monitoring occasion within a TTI, or both.
[0017] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a scrambling
sequence, a DCI format, a radio network temporary identifier
(RNTI), or a combination thereof, and where monitoring the downlink
control channel further may include operations, features, means, or
instructions for decoding the wakeup signal transmission based on
the scrambling sequence, the DCI format, the RNTI, or a combination
thereof.
[0018] A method for wireless communication at a base station is
described. The method may include configuring a UE with a first
search space configuration for monitoring a downlink control
channel while operating in a low power mode, configuring the UE
with a second search space configuration for monitoring the
downlink control channel while operating in an active mode, where
the second search space configuration is different from the first
search space configuration, and transmitting, to the UE, a wakeup
signal transmission using a wakeup signal resource according to the
first search space configuration based on the UE operating in the
low power mode.
[0019] An apparatus for wireless communication at a base station is
described. The apparatus may include a processor, memory coupled
with the processor, and instructions stored in the memory. The
instructions may be executable by the processor to cause the
apparatus to configure a UE with a first search space configuration
for monitoring a downlink control channel while operating in a low
power mode, configure the UE with a second search space
configuration for monitoring the downlink control channel while
operating in an active mode, where the second search space
configuration is different from the first search space
configuration, and transmit, to the UE, a wakeup signal
transmission using a wakeup signal resource according to the first
search space configuration based on the UE operating in the low
power mode.
[0020] Another apparatus for wireless communication at a base
station is described. The apparatus may include means for
configuring a UE with a first search space configuration for
monitoring a downlink control channel while operating in a low
power mode, configuring the UE with a second search space
configuration for monitoring the downlink control channel while
operating in an active mode, where the second search space
configuration is different from the first search space
configuration, and transmitting, to the UE, a wakeup signal
transmission using a wakeup signal resource according to the first
search space configuration based on the UE operating in the low
power mode.
[0021] A non-transitory computer-readable medium storing code for
wireless communication at a base station is described. The code may
include instructions executable by a processor to configure a UE
with a first search space configuration for monitoring a downlink
control channel while operating in a low power mode, configure the
UE with a second search space configuration for monitoring the
downlink control channel while operating in an active mode, where
the second search space configuration is different from the first
search space configuration, and transmit, to the UE, a wakeup
signal transmission using a wakeup signal resource according to the
first search space configuration based on the UE operating in the
low power mode.
[0022] Some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein may further include
operations, features, means, or instructions for transmitting, to
the UE and subsequent to transmitting the wakeup signal
transmission, a grant using a resource according to the second
search space configuration based on the UE operating in the active
mode subsequent to transmitting the wakeup signal transmission and
communicating with the UE based on the grant.
[0023] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein,
configuring the UE with the first search space configuration,
configuring the UE with the second search space configuration, or
both further may include operations, features, means, or
instructions for transmitting, to the UE, configuration signaling
configuring the UE with the first search space configuration, the
second search space configuration, or both.
[0024] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
search space configuration includes multiple CORESETs in a BWP,
multiple control channel monitoring occasions within a TTI, or
both.
[0025] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
search space configuration includes at least one resource
configuration parameter, and the transmitting the wakeup signal
transmission may be based on the at least one resource
configuration parameter.
[0026] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a starting
symbol within a TTI, and where transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource beginning at the starting symbol within
the TTI. In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a number of
symbols within the TTI, and where transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource beginning within the TTI at the starting
symbol and continuing for the number of symbols.
[0027] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a frequency
resource configuration parameter, a time resource configuration
parameter, or both, and where transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource based on the frequency resource
configuration parameter, the time resource configuration parameter,
or both.
[0028] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a scrambling
sequence, a DCI format, an RNTI, or a combination thereof, and
where transmitting the wakeup signal transmission further may
include operations, features, means, or instructions for
transmitting the wakeup signal transmission using the wakeup signal
resource based on the scrambling sequence, the DCI format, the
RNTI, or a combination thereof.
[0029] A method for wireless communication at a UE is described.
The method may include receiving configuration signaling
configuring the UE with a set of wakeup signal resource
configurations, receiving a configuration indicator indicating a
first wakeup signal resource configuration of the set of wakeup
signal resource configurations, and monitoring a wakeup signal
resource for a wakeup signal transmission based on the first wakeup
signal resource configuration.
[0030] An apparatus for wireless communication at a UE is
described. The apparatus may include a processor, memory in
electronic communication with the processor, and instructions
stored in the memory. The instructions may be executable by the
processor to cause the apparatus to receive configuration signaling
configuring the UE with a set of wakeup signal resource
configurations, receive a configuration indicator indicating a
first wakeup signal resource configuration of the set of wakeup
signal resource configurations, and monitor a wakeup signal
resource for a wakeup signal transmission based on the first wakeup
signal resource configuration.
[0031] Another apparatus for wireless communication at a UE is
described. The apparatus may include means for receiving
configuration signaling configuring the UE with a set of wakeup
signal resource configurations, receiving a configuration indicator
indicating a first wakeup signal resource configuration of the set
of wakeup signal resource configurations, and monitoring a wakeup
signal resource for a wakeup signal transmission based on the first
wakeup signal resource configuration.
[0032] A non-transitory computer-readable medium storing code for
wireless communication at a UE is described. The code may include
instructions executable by a processor to receive configuration
signaling configuring the UE with a set of wakeup signal resource
configurations, receive a configuration indicator indicating a
first wakeup signal resource configuration of the set of wakeup
signal resource configurations, and monitor a wakeup signal
resource for a wakeup signal transmission based on the first wakeup
signal resource configuration.
[0033] Some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein may further include
operations, features, means, or instructions for indexing a table,
based on the configuration indicator, for identifying at least one
resource configuration parameter of the first wakeup signal
resource configuration. In some examples of the method,
apparatuses, and non-transitory computer-readable medium described
herein, monitoring the wakeup signal resource may further include
operations, features, means, or instructions for monitoring the
wakeup signal resource for the wakeup signal transmission based on
the at least one resource configuration parameter.
[0034] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a starting
symbol within a transmission time interval, and monitoring the
wakeup signal resource further may include operations, features,
means, or instructions for monitoring the wakeup signal resource
for the wakeup signal transmission beginning at the starting symbol
within the transmission time interval. In some examples of the
method, apparatuses, and non-transitory computer-readable medium
described herein, the at least one resource configuration parameter
indicates a number of symbols within the transmission time
interval, and monitoring the wakeup signal resource further may
include operations, features, means, or instructions for monitoring
the wakeup signal resource for the wakeup signal transmission
beginning within the transmission time interval at the starting
symbol and continuing for the number of symbols.
[0035] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter may be a frequency
resource configuration parameter, a time resource configuration
parameter, or both, and monitoring the wakeup signal resource
further may include operations, features, means, or instructions
for monitoring the wakeup signal resource for the wakeup signal
transmission based on the frequency resource configuration
parameter, the time resource configuration parameter, or both. In
some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the at least one
resource configuration parameter may be the frequency resource
configuration parameter, and the frequency resource configuration
parameter may be a control resource set configuration parameter. In
other examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the at least one
resource configuration parameter may be the time resource
configuration parameter, and the time resource configuration
parameter indicates a search space configuration and a control
channel monitoring occasion within a transmission time interval. In
some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the search space
configuration indicates a transmission time interval periodicity
and an offset indicating a number of transmission time intervals
relative to a reference time.
[0036] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a scrambling
sequence, and monitoring the first wakeup signal resource further
may include operations, features, means, or instructions for
decoding the first wakeup signal resource based on the scrambling
sequence. In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the at
least one resource configuration parameter indicates a DCI format,
and monitoring the first wakeup signal resource further may include
operations, features, means, or instructions for decoding the first
wakeup signal resource based on the DCI format. In some examples of
the method, apparatuses, and non-transitory computer-readable
medium described herein, the at least one resource configuration
parameter indicates a radio network temporary identifier, and
monitoring the first wakeup signal resource further may include
operations, features, means, or instructions for decoding the first
wakeup signal resource based on the RNTI.
[0037] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a number of
different beams by which a wakeup signal may be transmitted within
a transmission time interval, and monitoring the wakeup signal
resource further may include operations, features, means, or
instructions for monitoring the wakeup signal resource for the
wakeup signal transmission within the transmission time interval
based on the number of different beams. In some examples of the
method, apparatuses, and non-transitory computer-readable medium
described herein, the first wakeup signal resource configuration
indicates a beam repetition factor for at least one beam by which a
wakeup signal may be transmitted within a transmission time
interval, and monitoring the wakeup signal resource further may
include operations, features, means, or instructions for monitoring
the wakeup signal resource for the wakeup signal transmission
within the transmission time interval based on the beam repetition
factor.
[0038] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a beam pattern for
at least one beam by which a wakeup signal may be transmitted
within a transmission time interval, and monitoring the wakeup
signal resource further may include operations, features, means, or
instructions for monitoring the wakeup signal resource for the
wakeup signal transmission within the transmission time interval
based on the beam pattern. In some examples of the method,
apparatuses, and non-transitory computer-readable medium described
herein, the first wakeup signal resource configuration indicates a
beam pattern for a set of different beams by which a wakeup signal
may be transmitted within a transmission time interval, and
monitoring the wakeup signal resource further may include
operations, features, means, or instructions for monitoring the
wakeup signal resource for the wakeup signal transmission within
the transmission time interval based on the beam pattern.
[0039] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, each
wakeup signal resource configuration of the set of wakeup signal
resource configurations corresponds to a different decoding
hypothesis of a set of decoding hypotheses, and monitoring the
wakeup signal resource further may include operations, features,
means, or instructions for identifying a first decoding hypothesis
of the set of decoding hypotheses based at least in part on the
first wakeup signal configuration and monitoring the wakeup signal
resource for the wakeup signal transmission based on the first
decoding hypothesis. In some examples of the method, apparatuses,
and non-transitory computer-readable medium described herein, each
decoding hypothesis of the set of decoding hypotheses corresponds
to a different beam pattern for at least one beam by which a wakeup
signal may be transmitted within a transmission time interval.
[0040] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration may be a downlink control
channel resource configuration.
[0041] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein,
monitoring the wakeup signal resource further may include
operations, features, means, or instructions for detecting a wakeup
signal for the UE within the wakeup signal resource, initiating a
wakeup procedure based on detecting the wakeup signal, and
monitoring a control channel subsequent to initiating the wakeup
procedure.
[0042] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein,
monitoring the control channel further may include operations,
features, means, or instructions for detecting, within the control
channel, a grant from a serving base station and communicating
based on the grant. In some examples of the method, apparatuses,
and non-transitory computer-readable medium described herein,
monitoring the control channel further may include operations,
features, means, or instructions for initiating a sleep procedure
based on determining that a grant has not been received within a
defined amount of time.
[0043] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein,
monitoring the control channel further may include operations,
features, means, or instructions for identifying a control channel
resource configuration of a serving base station and monitoring the
control channel based on the control channel resource
configuration. In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the
control channel resource configuration differs from the first
wakeup signal resource configuration.
[0044] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein,
monitoring the first wakeup signal resource further may include
operations, features, means, or instructions for monitoring a
downlink control channel for the wakeup signal transmission. In
some examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the first wakeup signal
configuration may be a reference signal configuration.
[0045] A method for wireless communication at a base station is
described. The method may include transmitting configuration
signaling configuring a UE with a set of wakeup signal resource
configurations, transmitting a configuration indicator indicating a
first wakeup signal resource configuration of the set of wakeup
signal resource configurations, and transmitting a wakeup signal
transmission using a wakeup signal resource based on the first
wakeup signal resource configuration.
[0046] An apparatus for wireless communication at a base station is
described. The apparatus may include a processor, memory in
electronic communication with the processor, and instructions
stored in the memory. The instructions may be executable by the
processor to cause the apparatus to transmit configuration
signaling configuring a UE with a set of wakeup signal resource
configurations, transmit a configuration indicator indicating a
first wakeup signal resource configuration of the set of wakeup
signal resource configurations, and transmit a wakeup signal
transmission using a wakeup signal resource based on the first
wakeup signal resource configuration.
[0047] Another apparatus for wireless communication at a base
station is described. The apparatus may include means for
transmitting configuration signaling configuring a UE with a set of
wakeup signal resource configurations, transmitting a configuration
indicator indicating a first wakeup signal resource configuration
of the set of wakeup signal resource configurations, and
transmitting a wakeup signal transmission using a wakeup signal
resource based on the first wakeup signal resource
configuration.
[0048] A non-transitory computer-readable medium storing code for
wireless communication at a base station is described. The code may
include instructions executable by a processor to transmit
configuration signaling configuring a UE with a set of wakeup
signal resource configurations, transmit a configuration indicator
indicating a first wakeup signal resource configuration of the set
of wakeup signal resource configurations, and transmit a wakeup
signal transmission using a wakeup signal resource based on the
first wakeup signal resource configuration.
[0049] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the
configuration signaling indicates a configuration of a table that
includes at least one resource configuration parameter for each
wakeup signal resource configuration of the set of wakeup signal
resource configurations.
[0050] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a starting symbol
within a transmission time interval, and transmitting the wakeup
signal transmission further may include operations, features,
means, or instructions for transmitting the wakeup signal
transmission using the wakeup signal resource beginning at the
starting symbol within the transmission time interval. In some
examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the first wakeup signal
resource configuration indicates a number of symbols within the
transmission time interval, and transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource beginning within the transmission time
interval at the starting symbol and continuing for the number of
symbols.
[0051] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a frequency resource
configuration parameter, a time resource configuration parameter,
or both, and transmitting the wakeup signal transmission further
may include operations, features, means, or instructions for
transmitting the wakeup signal transmission using the wakeup signal
resource based on the frequency resource configuration parameter,
the time resource configuration parameter, or both.
[0052] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a DCI format, a
scrambling sequence, an RNTI, or any combination thereof.
[0053] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a number of
different beams by which a wakeup signal may be transmitted within
a transmission time interval, and transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource within the transmission time interval
based on the number of different beams. In some examples of the
method, apparatuses, and non-transitory computer-readable medium
described herein, the first wakeup signal resource configuration
indicates a beam repetition factor for at least one beam by which a
wakeup signal may be transmitted within a transmission time
interval, and transmitting the wakeup signal transmission further
may include operations, features, means, or instructions for
transmitting the wakeup signal transmission using the wakeup signal
resource within the transmission time interval based on the beam
repetition factor.
[0054] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration indicates a beam pattern for
at least one beam by which a wakeup signal may be transmitted
within a transmission time interval, and transmitting the wakeup
signal transmission further may include operations, features,
means, or instructions for transmitting the wakeup signal
transmission using the wakeup signal resource within the
transmission time interval based on the beam pattern. In some
examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the first wakeup signal
resource configuration indicates a beam pattern for a set of
different beams by which a wakeup signal may be transmitted within
a transmission time interval, and transmitting the wakeup signal
transmission further may include operations, features, means, or
instructions for transmitting the wakeup signal transmission using
the wakeup signal resource within the transmission time interval
based on the beam pattern.
[0055] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, each
wakeup signal resource configuration of the set of wakeup signal
resource configurations corresponds to a different decoding
hypothesis of a set of decoding hypotheses. In some examples of the
method, apparatuses, and non-transitory computer-readable medium
described herein, each decoding hypothesis of the set of decoding
hypotheses corresponds to a different beam pattern for at least one
beam by which a wakeup signal may be transmitted within a
transmission time interval.
[0056] In some examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource may be a downlink control channel. In some
examples of the method, apparatuses, and non-transitory
computer-readable medium described herein, the first wakeup signal
resource configuration may be a reference signal resource
configuration. In other examples of the method, apparatuses, and
non-transitory computer-readable medium described herein, the first
wakeup signal resource configuration may be a downlink control
channel resource configuration.
BRIEF DESCRIPTION OF THE DRAWINGS
[0057] FIGS. 1 and 2 illustrate examples of wireless communications
systems that support wakeup signaling resource occasions in
accordance with aspects of the present disclosure.
[0058] FIG. 3 illustrates an example of a user equipment (UE)
operating timeline that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure.
[0059] FIG. 4 illustrates an example of a power level timeline for
a UE that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure.
[0060] FIG. 5 illustrates an example of a wakeup procedure timeline
for a wireless communications system that supports wakeup signaling
resource occasions in accordance with aspects of the present
disclosure.
[0061] FIGS. 6 and 7 illustrate examples of configurations for
wakeup signal resources that support wakeup signaling resource
occasions in accordance with aspects of the present disclosure.
[0062] FIG. 8 illustrates an example of a process flow that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure.
[0063] FIGS. 9 and 10 show block diagrams of devices that support
wakeup signaling resource occasions in accordance with aspects of
the present disclosure.
[0064] FIG. 11 shows a block diagram of a wakeup signaling
configuration module that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure.
[0065] FIG. 12 shows a diagram of a system including a device that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure.
[0066] FIGS. 13 and 14 show block diagrams of devices that support
wakeup signaling resource occasions in accordance with aspects of
the present disclosure.
[0067] FIG. 15 shows a block diagram of a wakeup signaling
configuration module that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure.
[0068] FIG. 16 shows a diagram of a system including a device that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure.
[0069] FIGS. 17 through 19 show flowcharts illustrating methods
that support wakeup signaling resource occasions in accordance with
aspects of the present disclosure.
DETAILED DESCRIPTION
[0070] Some wireless communications systems (e.g., millimeter wave
(mmW) systems) may support user equipment (UEs) operating in a
discontinuous reception (DRX) mode (e.g., a connected DRX (C-DRX)
mode). In a C-DRX mode, a UE may transition between an active state
for data transmission and reception and a sleep state for power
conservation. The UE may determine if data is available by
monitoring a control channel, such as a physical downlink control
channel (PDCCH). The PDCCH may carry or otherwise convey an
indication that a base station has data ready to transmit to the UE
or is scheduling the UE for data transmission. In some cases, to
reduce the frequency of the control channel monitoring, the UE may
monitor for a wakeup signal using a low complexity receiver while
in a low power mode. If the UE detects a wakeup signal transmitted
by the base station (e.g., on a downlink control channel or another
channel), the UE may transition to a higher power mode to monitor
the control channel for scheduling information. However, if the UE
does not detect a wakeup signal transmitted by the base station,
the UE may skip a full-power control channel monitoring opportunity
and instead return to a deep sleep mode, improving the power
savings at the UE.
[0071] In some cases, a base station may serve a large number of
UEs within a cell. In order to efficiently use wakeup signals, the
base station may differentiate the wakeup signals intended for each
UE or group of UEs based on wakeup signal resource configurations.
For example, each UE or group of UEs may be configured with a
specific wakeup signal resource configuration, where the wakeup
signal resource configuration indicates how the UE or group of UEs
monitors for wakeup signals, decodes wakeup signals, or both. If
the UE or group of UEs detects a wakeup signal transmitted
according to the wakeup signal resource configuration for that UE
or group of UEs, the UE or group of UEs may initiate a wakeup
procedure according to the wakeup signal. However, if a UE detects
a wakeup signal transmitted according to a different wakeup signal
resource configuration, the UE may determine that the wakeup signal
is intended for a different UE or group of UEs and may not perform
the wakeup procedure.
[0072] A wakeup signal resource configuration may indicate a number
of resource configuration parameters. These resource configuration
parameters may include time resource information (e.g., a start
symbol index and a duration for a monitoring period), frequency
resource information, decoding parameter information (e.g., a
scrambling sequence, downlink control information (DCI) format,
radio network temporary identifier (RNTI), decoding hypothesis, or
some combination of these for successfully decoding a wakeup
signal), beam sweeping information (e.g., a number of beams, beam
repetition factors, beam patterns, etc.), or some combination of
these parameters or other relevant parameters. If the UE receives a
wakeup signal in a monitoring occasion defined by the wakeup signal
resource configuration and successfully decodes the wakeup signal
according to decoding parameters defined by the wakeup signal
resource configuration, the UE may determine that the wakeup signal
is intended for the UE. Accordingly, the UE may perform a wakeup
procedure to transition to a higher power mode and monitor for
scheduling information. In this higher power mode (e.g., an active
power mode), the UE may operate according to different
configurations than the wakeup signal resource configuration. For
example, the wakeup signal resource configuration may be a first
search space configuration (e.g., a first search space set) and the
active power mode configuration may be a second search space
configuration (e.g., a second search space set).
[0073] Aspects of the disclosure are initially described in the
context of wireless communications systems. Additional aspects of
the disclosure are described with respect to timelines (e.g., a UE
operating timeline, a power level timeline for a UE, a wakeup
procedure timeline, etc.), configurations for wakeup signal
resources, and a process flow. Aspects of the disclosure are
further illustrated by and described with reference to apparatus
diagrams, system diagrams, and flowcharts that relate to wakeup
signaling resource occasions.
[0074] FIG. 1 illustrates an example of a wireless communications
system 100 that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure. The wireless
communications system 100 includes base stations 105, UEs 115, and
a core network 130. In some examples, the wireless communications
system 100 may be a Long Term Evolution (LTE) network, an
LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio
(NR) network. In some cases, wireless communications system 100 may
support enhanced broadband communications, ultra-reliable (e.g.,
mission critical) communications, low latency communications, or
communications with low-cost and low-complexity devices.
[0075] Base stations 105 may wirelessly communicate with UEs 115
via one or more base station antennas. Base stations 105 described
herein may include or may be referred to by those skilled in the
art as a base transceiver station, a radio base station, an access
point, a radio transceiver, a NodeB, an eNodeB (eNB), a
next-generation Node B or giga-nodeB (either of which may be
referred to as a gNB), a Home NodeB, a Home eNodeB, or some other
suitable terminology. Wireless communications system 100 may
include base stations 105 of different types (e.g., macro or small
cell base stations). The UEs 115 described herein may be able to
communicate with various types of base stations 105 and network
equipment including macro eNBs, small cell eNBs, gNBs, relay base
stations, and the like.
[0076] Each base station 105 may be associated with a particular
geographic coverage area 110 in which communications with various
UEs 115 is supported. Each base station 105 may provide
communication coverage for a respective geographic coverage area
110 via communication links 125, and communication links 125
between a base station 105 and a UE 115 may utilize one or more
carriers. Communication links 125 shown in wireless communications
system 100 may include uplink transmissions from a UE 115 to a base
station 105, or downlink transmissions from a base station 105 to a
UE 115. Downlink transmissions may also be called forward link
transmissions while uplink transmissions may also be called reverse
link transmissions.
[0077] The geographic coverage area 110 for a base station 105 may
be divided into sectors making up only a portion of the geographic
coverage area 110, and each sector may be associated with a cell.
For example, each base station 105 may provide communication
coverage for a macro cell, a small cell, a hot spot, or other types
of cells, or various combinations thereof. In some examples, a base
station 105 may be movable and therefore provide communication
coverage for a moving geographic coverage area 110. In some
examples, different geographic coverage areas 110 associated with
different technologies may overlap, and overlapping geographic
coverage areas 110 associated with different technologies may be
supported by the same base station 105 or by different base
stations 105. The wireless communications system 100 may include,
for example, a heterogeneous LTE/LTE-A/LTE-A Pro or NR network in
which different types of base stations 105 provide coverage for
various geographic coverage areas 110.
[0078] The term "cell" refers to a logical communication entity
used for communication with a base station 105 (e.g., over a
carrier), and may be associated with an identifier for
distinguishing neighboring cells (e.g., a physical cell identifier
(PCID), a virtual cell identifier (VCID)) operating via the same or
a different carrier. In some examples, a carrier may support
multiple cells, and different cells may be configured according to
different protocol types (e.g., machine-type communication (MTC),
narrowband Internet-of-Things (NB-IoT), enhanced mobile broadband
(eMBB), or others) that may provide access for different types of
devices. In some cases, the term "cell" may refer to a portion of a
geographic coverage area 110 (e.g., a sector) over which the
logical entity operates.
[0079] UEs 115 may be dispersed throughout the wireless
communications system 100, and each UE 115 may be stationary or
mobile. A UE 115 may also be referred to as a mobile device, a
wireless device, a remote device, a handheld device, or a
subscriber device, or some other suitable terminology, where the
"device" may also be referred to as a unit, a station, a terminal,
or a client. A UE 115 may also be a personal electronic device such
as a cellular phone, a personal digital assistant (PDA), a tablet
computer, a laptop computer, or a personal computer. In some
examples, a UE 115 may also refer to a wireless local loop (WLL)
station, an Internet of Things (IoT) device, an Internet of
Everything (IoE) device, or an MTC device, or the like, which may
be implemented in various articles such as appliances, vehicles,
meters, or the like.
[0080] Some UEs 115, such as MTC or IoT devices, may be low cost or
low complexity devices, and may provide for automated communication
between machines (e.g., via Machine-to-Machine (M2M)
communication). M2M communication or MTC may refer to data
communication technologies that allow devices to communicate with
one another or a base station 105 without human intervention. In
some examples, M2M communication or MTC may include communications
from devices that integrate sensors or meters to measure or capture
information and relay that information to a central server or
application program that can make use of the information or present
the information to humans interacting with the program or
application. Some UEs 115 may be designed to collect information or
enable automated behavior of machines. Examples of applications for
MTC devices include smart metering, inventory monitoring, water
level monitoring, equipment monitoring, healthcare monitoring,
wildlife monitoring, weather and geological event monitoring, fleet
management and tracking, remote security sensing, physical access
control, and transaction-based business charging.
[0081] Some UEs 115 may be configured to employ operating modes
that reduce power consumption, such as half-duplex communications
(e.g., a mode that supports one-way communication via transmission
or reception, but not transmission and reception simultaneously).
In some examples half-duplex communications may be performed at a
reduced peak rate. Other power conservation techniques for UEs 115
include entering a power saving "deep sleep" mode when not engaging
in active communications, or operating over a limited bandwidth
(e.g., according to narrowband communications). In some cases, UEs
115 may be designed to support critical functions (e.g., mission
critical functions), and a wireless communications system 100 may
be configured to provide ultra-reliable communications for these
functions.
[0082] In some cases, a UE 115 may also be able to communicate
directly with other UEs 115 (e.g., using a peer-to-peer (P2P) or
device-to-device (D2D) protocol). One or more of a group of UEs 115
utilizing D2D communications may be within the geographic coverage
area 110 of a base station 105. Other UEs 115 in such a group may
be outside the geographic coverage area 110 of a base station 105,
or be otherwise unable to receive transmissions from a base station
105. In some cases, groups of UEs 115 communicating via D2D
communications may utilize a one-to-many (1:M) system in which each
UE 115 transmits to every other UE 115 in the group. In some cases,
a base station 105 facilitates the scheduling of resources for D2D
communications. In other cases, D2D communications are carried out
between UEs 115 without the involvement of a base station 105.
[0083] Base stations 105 may communicate with the core network 130
and with one another. For example, base stations 105 may interface
with the core network 130 through backhaul links 132 (e.g., via an
S1, N2, N3, or other interface). Base stations 105 may communicate
with one another over backhaul links 134 (e.g., via an X2, Xn, or
other interface) either directly (e.g., directly between base
stations 105) or indirectly (e.g., via core network 130).
[0084] The core network 130 may provide user authentication, access
authorization, tracking, Internet Protocol (IP) connectivity, and
other access, routing, or mobility functions. The core network 130
may be an evolved packet core (EPC), which may include at least one
mobility management entity (MME), at least one serving gateway
(S-GW), and at least one Packet Data Network (PDN) gateway (P-GW).
The MME may manage non-access stratum (e.g., control plane)
functions such as mobility, authentication, and bearer management
for UEs 115 served by base stations 105 associated with the EPC.
User IP packets may be transferred through the S-GW, which itself
may be connected to the P-GW. The P-GW may provide IP address
allocation as well as other functions. The P-GW may be connected to
the network operators IP services. The operators IP services may
include access to the Internet, Intranet(s), an IP Multimedia
Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.
[0085] At least some of the network devices, such as a base station
105, may include subcomponents such as an access network entity,
which may be an example of an access node controller (ANC). Each
access network entity may communicate with UEs 115 through a number
of other access network transmission entities, which may be
referred to as a radio head, a smart radio head, or a
transmission/reception point (TRP). In some configurations, various
functions of each access network entity or base station 105 may be
distributed across various network devices (e.g., radio heads and
access network controllers) or consolidated into a single network
device (e.g., a base station 105).
[0086] Wireless communications system 100 may operate using one or
more frequency bands, typically in the range of 300 MHz to 300 GHz.
Generally, the region from 300 MHz to 3 GHz is known as the
ultra-high frequency (UHF) region or decimeter band, since the
wavelengths range from approximately one decimeter to one meter in
length. UHF waves may be blocked or redirected by buildings and
environmental features. However, the waves may penetrate structures
sufficiently for a macro cell to provide service to UEs 115 located
indoors. Transmission of UHF waves may be associated with smaller
antennas and shorter range (e.g., less than 100 km) compared to
transmission using the smaller frequencies and longer waves of the
high frequency (HF) or very high frequency (VHF) portion of the
spectrum below 300 MHz.
[0087] Wireless communications system 100 may also operate in a
super high frequency (SHF) region using frequency bands from 3 GHz
to 30 GHz, also known as the centimeter band. The SHF region
includes bands such as the 5 GHz industrial, scientific, and
medical (ISM) bands, which may be used opportunistically by devices
that can tolerate interference from other users.
[0088] Wireless communications system 100 may also operate in an
extremely high frequency (EHF) region of the spectrum (e.g., from
30 GHz to 300 GHz), also known as the millimeter band. In some
examples, wireless communications system 100 may support millimeter
wave (mmW) communications between UEs 115 and base stations 105,
and EHF antennas of the respective devices may be even smaller and
more closely spaced than UHF antennas. In some cases, this may
facilitate use of antenna arrays within a UE 115. However, the
propagation of EHF transmissions may be subject to even greater
atmospheric attenuation and shorter range than SHF or UHF
transmissions. Techniques disclosed herein may be employed across
transmissions that use one or more different frequency regions, and
designated use of bands across these frequency regions may differ
by country or regulating body.
[0089] In some cases, wireless communications system 100 may
utilize both licensed and unlicensed radio frequency spectrum
bands. For example, wireless communications system 100 may employ
License Assisted Access (LAA), LTE-Unlicensed (LTE-U) radio access
technology, or NR technology in an unlicensed band such as the 5
GHz ISM band. When operating in unlicensed radio frequency spectrum
bands, wireless devices such as base stations 105 and UEs 115 may
employ listen-before-talk (LBT) procedures to ensure a frequency
channel is clear before transmitting data. In some cases,
operations in unlicensed bands may be based on a carrier
aggregation (CA) configuration in conjunction with component
carriers (CCs) operating in a licensed band (e.g., LAA). Operations
in unlicensed spectrum may include downlink transmissions, uplink
transmissions, peer-to-peer transmissions, or a combination of
these. Duplexing in unlicensed spectrum may be based on frequency
division duplexing (FDD), time division duplexing (TDD), or a
combination of both.
[0090] In some examples, base station 105 or UE 115 may be equipped
with multiple antennas, which may be used to employ techniques such
as transmit diversity, receive diversity, multiple-input
multiple-output (MIMO) communications, or beamforming. For example,
wireless communications system 100 may use a transmission scheme
between a transmitting device (e.g., a base station 105) and a
receiving device (e.g., a UE 115), where the transmitting device is
equipped with multiple antennas and the receiving devices are
equipped with one or more antennas. MIMO communications may employ
multipath signal propagation to increase the spectral efficiency by
transmitting or receiving multiple signals via different spatial
layers, which may be referred to as spatial multiplexing. The
multiple signals may, for example, be transmitted by the
transmitting device via different antennas or different
combinations of antennas. Likewise, the multiple signals may be
received by the receiving device via different antennas or
different combinations of antennas. Each of the multiple signals
may be referred to as a separate spatial stream, and may carry bits
associated with the same data stream (e.g., the same codeword) or
different data streams. Different spatial layers may be associated
with different antenna ports used for channel measurement and
reporting. MIMO techniques include single-user MIMO (SU-MIMO) where
multiple spatial layers are transmitted to the same receiving
device, and multiple-user MIMO (MU-MIMO) where multiple spatial
layers are transmitted to multiple devices.
[0091] Beamforming, which may also be referred to as spatial
filtering, directional transmission, or directional reception, is a
signal processing technique that may be used at a transmitting
device or a receiving device (e.g., a base station 105 or a UE 115)
to shape or steer an antenna beam (e.g., a transmit beam or receive
beam) along a spatial path between the transmitting device and the
receiving device. Beamforming may be achieved by combining the
signals communicated via antenna elements of an antenna array such
that signals propagating at particular orientations with respect to
an antenna array experience constructive interference while others
experience destructive interference. The adjustment of signals
communicated via the antenna elements may include a transmitting
device or a receiving device applying certain amplitude and phase
offsets to signals carried via each of the antenna elements
associated with the device. The adjustments associated with each of
the antenna elements may be defined by a beamforming weight set
associated with a particular orientation (e.g., with respect to the
antenna array of the transmitting device or receiving device, or
with respect to some other orientation).
[0092] In one example, a base station 105 may use multiple antennas
or antenna arrays to conduct beamforming operations for directional
communications with a UE 115. For instance, some signals (e.g.
synchronization signals, reference signals, beam selection signals,
or other control signals) may be transmitted by a base station 105
multiple times in different directions, which may include a signal
being transmitted according to different beamforming weight sets
associated with different directions of transmission. Transmissions
in different beam directions may be used to identify (e.g., by the
base station 105 or a receiving device, such as a UE 115) a beam
direction for subsequent transmission and/or reception by the base
station 105. Some signals, such as data signals associated with a
particular receiving device, may be transmitted by a base station
105 in a single beam direction (e.g., a direction associated with
the receiving device, such as a UE 115). In some examples, the beam
direction associated with transmissions along a single beam
direction may be determined based at least in in part on a signal
that was transmitted in different beam directions. For example, a
UE 115 may receive one or more of the signals transmitted by the
base station 105 in different directions, and the UE 115 may report
to the base station 105 an indication of the signal it received
with a highest signal quality, or an otherwise acceptable signal
quality. Although these techniques are described with reference to
signals transmitted in one or more directions by a base station
105, a UE 115 may employ similar techniques for transmitting
signals multiple times in different directions (e.g., for
identifying a beam direction for subsequent transmission or
reception by the UE 115), or transmitting a signal in a single
direction (e.g., for transmitting data to a receiving device).
[0093] A receiving device (e.g., a UE 115, which may be an example
of a mmW receiving device) may try multiple receive beams when
receiving various signals from the base station 105, such as
synchronization signals, reference signals, beam selection signals,
or other control signals. For example, a receiving device may try
multiple receive directions by receiving via different antenna
subarrays, by processing received signals according to different
antenna subarrays, by receiving according to different receive
beamforming weight sets applied to signals received at a plurality
of antenna elements of an antenna array, or by processing received
signals according to different receive beamforming weight sets
applied to signals received at a plurality of antenna elements of
an antenna array, any of which may be referred to as "listening"
according to different receive beams or receive directions. In some
examples a receiving device may use a single receive beam to
receive along a single beam direction (e.g., when receiving a data
signal). The single receive beam may be aligned in a beam direction
determined based at least in part on listening according to
different receive beam directions (e.g., a beam direction
determined to have a highest signal strength, highest
signal-to-noise ratio, or otherwise acceptable signal quality based
at least in part on listening according to multiple beam
directions).
[0094] In some cases, the antennas of a base station 105 or UE 115
may be located within one or more antenna arrays, which may support
MIMO operations, or transmit or receive beamforming. For example,
one or more base station antennas or antenna arrays may be
co-located at an antenna assembly, such as an antenna tower. In
some cases, antennas or antenna arrays associated with a base
station 105 may be located in diverse geographic locations. A base
station 105 may have an antenna array with a number of rows and
columns of antenna ports that the base station 105 may use to
support beamforming of communications with a UE 115. Likewise, a UE
115 may have one or more antenna arrays that may support various
MIMO or beamforming operations.
[0095] In some cases, wireless communications system 100 may be a
packet-based network that operate according to a layered protocol
stack. In the user plane, communications at the bearer or Packet
Data Convergence Protocol (PDCP) layer may be IP-based. A Radio
Link Control (RLC) layer may in some cases perform packet
segmentation and reassembly to communicate over logical channels. A
Medium Access Control (MAC) layer may perform priority handling and
multiplexing of logical channels into transport channels. The MAC
layer may also use hybrid automatic repeat request (HARQ) to
provide retransmission at the MAC layer to improve link efficiency.
In the control plane, the Radio Resource Control (RRC) protocol
layer may provide establishment, configuration, and maintenance of
an RRC connection between a UE 115 and a base station 105 or core
network 130 supporting radio bearers for user plane data. At the
Physical (PHY) layer, transport channels may be mapped to physical
channels.
[0096] In some cases, UEs 115 and base stations 105 may support
retransmissions of data to increase the likelihood that data is
received successfully. HARQ feedback is one technique of increasing
the likelihood that data is received correctly over a communication
link 125. HARQ may include a combination of error detection (e.g.,
using a cyclic redundancy check (CRC)), forward error correction
(FEC), and retransmission (e.g., automatic repeat request (ARQ)).
HARQ may improve throughput at the MAC layer in poor radio
conditions (e.g., signal-to-noise conditions). In some cases, a
wireless device may support same-slot HARQ feedback, where the
device may provide HARQ feedback in a specific slot for data
received in a previous symbol in the slot. In other cases, the
device may provide HARQ feedback in a subsequent slot, or according
to some other time interval.
[0097] Time intervals in LTE or NR may be expressed in multiples of
a basic time unit, which may, for example, refer to a sampling
period of T.sub.s= 1/30,720,000 seconds. Time intervals of a
communications resource may be organized according to radio frames
each having a duration of 10 milliseconds (ms), where the frame
period may be expressed as T.sub.f=307,200 T.sub.s. The radio
frames may be identified by a system frame number (SFN) ranging
from 0 to 1023. Each frame may include 10 subframes numbered from 0
to 9, and each subframe may have a duration of 1 ms. A subframe may
be further divided into 2 slots each having a duration of 0.5 ms,
and each slot may contain 6 or 7 modulation symbol periods (e.g.,
depending on the length of the cyclic prefix prepended to each
symbol period). Excluding the cyclic prefix, each symbol period may
contain 2048 sampling periods. In some cases, a subframe may be the
smallest scheduling unit of the wireless communications system 100,
and may be referred to as a transmission time interval (TTI). In
other cases, a smallest scheduling unit of the wireless
communications system 100 may be shorter than a subframe or may be
dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) or
in selected component carriers using sTTIs).
[0098] In some wireless communications systems, a slot may further
be divided into multiple mini-slots containing one or more symbols.
In some instances, a symbol of a mini-slot or a mini-slot may be
the smallest unit of scheduling. Each symbol may vary in duration
depending on the subcarrier spacing or frequency band of operation,
for example. Further, some wireless communications systems may
implement slot aggregation in which multiple slots or mini-slots
are aggregated together and used for communication between a UE 115
and a base station 105.
[0099] The term "carrier" refers to a set of radio frequency
spectrum resources having a defined physical layer structure for
supporting communications over a communication link 125. For
example, a carrier of a communication link 125 may include a
portion of a radio frequency spectrum band that is operated
according to physical layer channels for a given radio access
technology. Each physical layer channel may carry user data,
control information, or other signaling. A carrier may be
associated with a pre-defined frequency channel (e.g., an E-UTRA
absolute radio frequency channel number (EARFCN)), and may be
positioned according to a channel raster for discovery by UEs 115.
Carriers may be downlink or uplink (e.g., in an FDD mode), or be
configured to carry downlink and uplink communications (e.g., in a
TDD mode). In some examples, signal waveforms transmitted over a
carrier may be made up of multiple sub-carriers (e.g., using
multi-carrier modulation (MCM) techniques such as OFDM or
DFT-s-OFDM).
[0100] The organizational structure of the carriers may be
different for different radio access technologies (e.g., LTE,
LTE-A, LTE-A Pro, NR, etc.). For example, communications over a
carrier may be organized according to TTIs or slots, each of which
may include user data as well as control information or signaling
to support decoding the user data. A carrier may also include
dedicated acquisition signaling (e.g., synchronization signals or
system information, etc.) and control signaling that coordinates
operation for the carrier. In some examples (e.g., in a carrier
aggregation configuration), a carrier may also have acquisition
signaling or control signaling that coordinates operations for
other carriers.
[0101] Physical channels may be multiplexed on a carrier according
to various techniques. A physical control channel and a physical
data channel may be multiplexed on a downlink carrier, for example,
using time division multiplexing (TDM) techniques, frequency
division multiplexing (FDM) techniques, or hybrid TDM-FDM
techniques. In some examples, control information transmitted in a
physical control channel may be distributed between different
control regions in a cascaded manner (e.g., between a common
control region or common search space and one or more UE-specific
control regions or UE-specific search spaces).
[0102] A carrier may be associated with a particular bandwidth of
the radio frequency spectrum, and in some examples the carrier
bandwidth may be referred to as a "system bandwidth" of the carrier
or the wireless communications system 100. For example, the carrier
bandwidth may be one of a number of predetermined bandwidths for
carriers of a particular radio access technology (e.g., 1.4, 3, 5,
10, 15, 20, 40, or 80 MHz). In some examples, each served UE 115
may be configured for operating over portions or all of the carrier
bandwidth. In other examples, some UEs 115 may be configured for
operation using a narrowband protocol type that is associated with
a predefined portion or range (e.g., set of subcarriers or RBs)
within a carrier (e.g., "in-band" deployment of a narrowband
protocol type).
[0103] In a system employing MCM techniques, a resource element may
consist of one symbol period (e.g., a duration of one modulation
symbol) and one subcarrier, where the symbol period and subcarrier
spacing are inversely related. The number of bits carried by each
resource element may depend on the modulation scheme (e.g., the
order of the modulation scheme). Thus, the more resource elements
that a UE 115 receives and the higher the order of the modulation
scheme, the higher the data rate may be for the UE 115. In MIMO
systems, a wireless communications resource may refer to a
combination of a radio frequency spectrum resource, a time
resource, and a spatial resource (e.g., spatial layers), and the
use of multiple spatial layers may further increase the data rate
for communications with a UE 115.
[0104] Devices of the wireless communications system 100 (e.g.,
base stations 105 or UEs 115) may have a hardware configuration
that supports communications over a particular carrier bandwidth or
may be configurable to support communications over one of a set of
carrier bandwidths. In some examples, the wireless communications
system 100 may include base stations 105 and/or UEs 115 that can
support simultaneous communications via carriers associated with
more than one different carrier bandwidth.
[0105] Wireless communications system 100 may support communication
with a UE 115 on multiple cells or carriers, a feature which may be
referred to as CA or multi-carrier operation. A UE 115 may be
configured with multiple downlink CCs and one or more uplink CCs
according to a carrier aggregation configuration. Carrier
aggregation may be used with both FDD and TDD component
carriers.
[0106] In some cases, wireless communications system 100 may
utilize enhanced component carriers (eCCs). An eCC may be
characterized by one or more features including wider carrier or
frequency channel bandwidth, shorter symbol duration, shorter TTI
duration, or modified control channel configuration. In some cases,
an eCC may be associated with a carrier aggregation configuration
or a dual connectivity configuration (e.g., when multiple serving
cells have a suboptimal or non-ideal backhaul link). An eCC may
also be configured for use in unlicensed spectrum or shared
spectrum (e.g., where more than one operator is allowed to use the
spectrum). An eCC characterized by wide carrier bandwidth may
include one or more segments that may be utilized by UEs 115 that
are not capable of monitoring the whole carrier bandwidth or are
otherwise configured to use a limited carrier bandwidth (e.g., to
conserve power).
[0107] In some cases, an eCC may utilize a different symbol
duration than other CCs, which may include use of a reduced symbol
duration as compared with symbol durations of the other CCs. A
shorter symbol duration may be associated with increased spacing
between adjacent subcarriers. A device, such as a UE 115 or base
station 105, utilizing eCCs may transmit wideband signals (e.g.,
according to frequency channel or carrier bandwidths of 20, 40, 60,
80 MHz, etc.) at reduced symbol durations (e.g., 16.67
microseconds). A TTI in eCC may consist of one or multiple symbol
periods. In some cases, the TTI duration (that is, the number of
symbol periods in a TTI) may be variable.
[0108] Wireless communications systems such as an NR system may
utilize any combination of licensed, shared, and unlicensed
spectrum bands, among others. The flexibility of eCC symbol
duration and subcarrier spacing may allow for the use of eCC across
multiple spectrums. In some examples, NR shared spectrum may
increase spectrum utilization and spectral efficiency, specifically
through dynamic vertical (e.g., across the frequency domain) and
horizontal (e.g., across the time domain) sharing of resources.
[0109] Some wireless communications systems 100 (e.g., mmW systems)
may support UEs 115 operating in a C-DRX mode. In a C-DRX mode, a
UE 115 may transition between an active state (e.g., an active
mode) for data transmission and reception and a sleep state (e.g.,
an inactive or low power mode) for power conservation. The UE 115
may determine if data is available by monitoring a control channel,
such as a PDCCH. The PDCCH may carry or otherwise convey an
indication that a base station 105 has data ready to transmit to
the UE 115 or is scheduling the UE 115 for data transmission. In
some cases, to reduce the frequency of control channel monitoring,
the UE 115 may monitor for a wakeup signal using a low complexity
receiver while in a low power mode. If the UE 115 detects a wakeup
signal transmitted by the base station 105, the UE 115 may
transition to a higher power mode to monitor the control channel
for scheduling information. However, if the UE 115 does not detect
a wakeup signal transmitted by the base station 105, the UE 115 may
skip a control channel monitoring opportunity and instead return to
a deep sleep mode, improving the power savings at the UE 115.
[0110] In some cases, a base station 105 may serve a large number
of UEs 115 within a cell. In order to efficiently use wakeup
signals, the base station 105 may differentiate the wakeup signals
intended for each UE 115 or group of UEs 115 based on wakeup signal
resource configurations. For example, each UE 115 may be configured
with a specific wakeup signal resource configuration, where the
wakeup signal resource configuration indicates how the UE 115
monitors for wakeup signals, decodes wakeup signals, or both. If
the UE 115 detects a wakeup signal transmitted according to the
wakeup signal resource configuration for that UE 115, the UE 115
may initiate a wakeup procedure according to the wakeup signal.
However, if a UE 115 detects a wakeup signal transmitted according
to a different wakeup signal resource configuration, the UE 115 may
determine that the wakeup signal is intended for a different UE 115
or group of UEs 115 and may not perform the wakeup procedure.
[0111] A wakeup signal resource configuration may indicate a number
of resource configuration parameters. These resource configuration
parameters may include time resource information (e.g., a start
symbol index and a duration for a monitoring window), frequency
resource information for a monitoring window, decoding parameter
information (e.g., a scrambling sequence, DCI format, RNTI,
decoding hypothesis, or some combination of these for successfully
decoding a wakeup signal), beam sweeping information (e.g., a
number of beams, beam repetition factors, beam patterns, etc., for
receiving a wakeup signal), or some combination of these parameters
or other relevant parameters. If the UE 115 receives a wakeup
signal in a monitoring occasion defined by the wakeup signal
resource configuration and successfully decodes the wakeup signal
according to decoding parameters defined by the wakeup signal
resource configuration, the UE 115 may determine that the wakeup
signal is intended for the UE 115. Accordingly, the UE 115 may
perform a wakeup procedure to transition to a higher power mode and
monitor for scheduling information. In this higher power mode
(e.g., an active power mode), the UE 115 may operate according to
different configurations than the wakeup signal resource
configuration. By differentiating wakeup signals for different UEs
115 using these wakeup signal resource configurations, a wireless
communications system 100 may support improved power savings at the
UEs 115.
[0112] FIG. 2 illustrates an example of a wireless communications
system 200 that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure. The wireless
communications system 200 may be an example of a wireless
communications system 100 and may contain base station 105-a, UE
115-a, and UE 115-b, which may be examples of the corresponding
wireless devices described with reference to FIG. 1. Base station
105-a may provide network coverage for UEs 115 within geographic
coverage area 110-a. In some cases, UEs 115 may support C-DRX
operation with wakeup signals 210 for improved power efficiency.
For example, a UE 115 may operate in a low power mode until
signaled, via a wakeup signal 210, to transition into a higher
power mode to support data transmission and reception. These wakeup
signals 210 may be examples of reference signal-type signals or
PDCCH-type signals. UEs 115 (e.g., UE 115-a and UE 115-b) may
differentiate between wakeup signals 210 transmitted by base
station 105-a based on different parameters or configurations
according to the type of wakeup signal 210.
[0113] In the wireless communications system 200 (e.g., an mmW
system supporting beamforming), base station 105-a may transmit
wakeup signals 210 using a beam sweeping procedure. For example,
base station 105-a may transmit wakeup signals 210 on a downlink
channel 205 (e.g., a downlink control channel) using a number of
different downlink transmit beams 215. Base station 105-a may sweep
through N different transmit beams for transmitting the wakeup
signaling to improve the reception reliability at a UE 115. For
example, when a UE 115 is in a low power mode (e.g., a sleep mode),
the UE 115 may experience some level of beam degradation, such as
beam misalignment, beam blocking, etc. To reduce the probability
that the UE 115 misses a wakeup signal 210 transmitted by base
station 105-a due to this beam degradation, the base station 105-a
may use a variety of beam directions, beam widths, or both for
transmitting the wakeup signal 210 to the UE 115. If the UE 115
successfully receives one or more of the wakeup signals 210
transmitted in the beam sweeping procedure, the UE 115 may perform
a wakeup procedure and transition to a higher power level to
support data transmission and reception. The number of downlink
transmit beams, N, or the directions of the beams in the beam sweep
may be dynamically determined by base station 105-a. UEs 115 may
attempt to receive the wakeup signals 210 using a number of
downlink receive beams 220. For example, UE 115-a may monitor for
wakeup signaling using downlink receive beams 220-a and UE 115-b
may monitor for wakeup signaling using downlink receive beams
220-b.
[0114] UEs 115 may be configured to receive wakeup signals 210
according to particular configuration parameters and a
configuration framework. In some cases, a UE 115 may be
pre-configured for a specific configuration framework, which may be
referred to as a wakeup signal resource configuration. In other
cases, base station 105-a may transmit an indication (e.g., a
configuration indicator) of the configuration framework for the UE
115. In a first example, the configuration framework for a UE 115
may be an example of a downlink control channel (e.g., a PDCCH)
resource configuration. For example, the downlink control channel
resource configuration may include one or more control resource
sets (CORESETs), one or more search spaces, one or more monitoring
occasions, or a combination thereof. In a second example, the
configuration framework for the UE 115 may be an example of a
reference signal (e.g., a channel state information reference
signal (CSI-RS), tracking reference signal (TRS), demodulation
reference signal (DMRS), etc.) configuration.
[0115] Each wakeup signal 210 may either be a UE-specific or
group-specific wakeup signal 210. For example, base station 105-a
may transmit a UE-specific wakeup signal 210 to initiate a wakeup
procedure at one particular UE 115. That is, each UE 115 may have a
dedicated wakeup signal 210, dedicated signaling occasions, or
both. This may result in a large network overhead (e.g., for base
station 105-a to transmit wakeup signals 210 for each UE 115
scheduled to wake up) but highly flexible and efficient wakeup
signaling for improved UE power saving. Base station 105-a may
transmit wakeup signal 210-a on downlink channel 205-a to wake up
UE 115-a and wakeup signal 210-b on downlink channel 205-b to wake
up UE 115-b. If UE 115-b detects wakeup signal 210-a, UE 115-b may
identify that the wakeup signal 210-a is intended for a different
UE 115 and may not perform a wakeup procedure.
[0116] Alternatively, base station 105-a may transmit a
group-specific wakeup signal 210 to wake up both UE 115-a and UE
115-b if both of these UEs 115 are in a same UE group. That is,
each pre-defined or dynamically defined group of UEs 115 may share
the same wakeup signal 210, signaling occasions, or both. This may
result in a low network overhead, but one or more UEs 115 may wake
up based on a group-specific wakeup signal 210 even if the wakeup
signal 210 is intended for another UE 115 in the same group. A UE
115 waking up even if there is no data to transmit or receive based
on a group-specific wakeup signal 210 may incur a power
penalty.
[0117] To support a large number of UEs 115 within a cell (e.g.,
the geographic coverage area 110-a), UEs 115 or UE groups may share
the available resources for monitoring wakeup signals 210. Base
station 105-a may multiplex wakeup signals 210 such that the
available resources are efficiently used to support wakeup
procedures for multiple UEs 115 with minimal power penalties. That
is, by configuring UEs 115 with different resources for wakeup
occasions, base station 105-a may initiate wakeup procedures with
different UEs 115 during small time windows without unnecessarily
waking up other UEs 115 or groups of UEs 115.
[0118] FIG. 3 illustrates an example of a UE operating timeline 300
that supports wakeup signaling resource occasions in accordance
with aspects of the present disclosure. The UE operating timeline
300 may correspond to functionality performed by a UE 115 described
with reference to FIGS. 1 and 2. The UE 115 may utilize C-DRX
operations to achieve power savings during periods of traffic
inactivity based on a capability or configuration of the UE 115. In
some cases, the UE operating timeline 300 corresponds to UE
operations in a legacy wireless communications system. For further
power savings in a wireless communications system 100 or 200, a UE
115 may additionally support wakeup signals to trigger ramping-up
power for UE "ON" durations.
[0119] A UE 115 may operate in a number of different power modes to
support transmission and reception of data while achieving power
savings. For example, in an active duration 305-a, a UE 115 may
operate in a high or standard power mode (e.g., as compared to a
low power mode or a sleep mode of the UE 115). During the active
duration 305-a, the UE 115 may receive signals during any number of
receive durations 310 and may transmit signals during any number of
transmit durations 315. For example, the UE 115 may receive
downlink data from a base station 105 using a receiver (e.g., a
full-power or standard receiver), transmit uplink data to the base
station 105, participate in D2D communications, or perform any
combination of these operations. The UE 115 may remain in the high
or standard power mode for an inactive period 320 following the
active duration 305-a. During this inactive period, the UE 115 may
not detect any PDCCH signaling. The UE 115 may initiate an
inactivity timer at the start of the inactive period 320 (i.e., the
end of the active duration 305-a). If the UE 115 receives
additional signals (e.g., PDCCH signals) or transmits additional
signals before expiration of the inactivity timer, the UE 115 may
re-enter an additional active duration 305 and may reset the
inactivity timer to restart at the end of this additional active
duration 305. Otherwise, if the inactivity timer expires at 325,
the UE 115 may ramp-down its power and enter a low power mode or
sleep mode (e.g., a UE "OFF" duration). During an OFF duration, the
UE 115 may not transmit or receive signals due to the current UE
power level. In this way, during traffic inactivity, the UE 115 may
switch to C-DRX operation to achieve significant power savings.
[0120] Based on configured C-DRX cycles, the UE 115 may
periodically or aperiodically wake up from the low power mode into
an ON duration. During the ON duration, the UE 115 may monitor the
PDCCH for any signaling transmitted to the UE 115 (e.g., DCI
messages, grants, etc.). If the UE 115 does not detect any PDCCH
signaling for the UE 115, the UE 115 may return to an OFF duration
(i.e., go back to sleep) for the remainder of the C-DRX cycle
following the ON duration with no PDCCH detected 330. The UE 115
may then wake up for the next ON duration and repeat the PDCCH
monitoring. The length of time between each ON duration may stay
the same or change based on one or more timers. For example, the UE
115 may initially wake up from the OFF mode at regular intervals
defined by a short C-DRX cycle 335. However, upon expiration of a
short C-DRX timer at 340 (e.g., where the short C-DRX timer may be
activated at the end of the inactive period 320), the UE 115 may
switch from the short C-DRX cycle 335 to a long C-DRX cycle 345 for
further power savings. During the long C-DRX cycles 345, the UE 115
may wake up periodically for ON durations, where the time intervals
between ON durations for the long C-DRX cycles 345 are longer than
the time intervals between ON durations during the short C-DRX
cycles 335. In some cases, a UE 115 may support additional C-DRX
cycle lengths and corresponding timers.
[0121] If, during an ON duration, the UE 115 detects a PDCCH signal
for the UE 115, the UE 115 may perform a wakeup procedure and may
terminate the C-DRX mode (e.g., either the short C-DRX mode or the
long C-DRX mode). For example, the UE 115 may enter an active
duration 305-b based on an ON duration with PDCCH detected 350. In
some cases, the PDCCH signal may schedule data for the UE 115, and
the UE 115 may operate according to a number of receive durations
310, transmit durations 315, or both during the active duration
305-b according to the data scheduling. The UE 115 may remain in
the high or standard power mode for data transmission and reception
during the active duration 305-b.
[0122] In some cases, the UE operating timeline 300 may be based on
a number of configuration parameters for the UE 115. These
configuration parameters may include an inactivity timer (e.g., a
length of time for an inactive period 320, after which the UE 115
powers down), a short DRX timer (e.g., a length of time for
operating according to a short C-DRX cycle 335 before switching to
a long C-DRX cycle 345), a short DRX cycle (e.g., the length of the
short C-DRX cycle 335 defining a first periodicity of ON
durations), a long DRX cycle (e.g., the length of the long C-DRX
cycle 345 defining a second periodicity of ON durations), or any
combination of these or other relevant parameters for DRX
operation. In some cases, a UE 115 may be pre-configured with these
configuration parameters. In other cases, a base station 105 may
configure the UE 115 with configuration parameters. Additionally,
the durations, periods, and cycles described herein may span any
length of time (e.g., a number of symbols, slots, subframes,
frames, etc.) based on the UE or base station configuration.
[0123] To further improve the power savings at a UE 115, the UE 115
may implement wakeup signals in conjunction with C-DRX operations.
Using the a low-power receiver, the UE 115 may monitor for wakeup
signals to indicate subsequent data scheduling. To handle a large
number of UEs operating within a wireless communications system,
the UEs may be configured with specific wakeup signaling resource
occasions and parameters. Using these parameters, a UE 115 may
identify whether a wakeup signal is for that UE 115, and may not
wake up based on wakeup signals intended for other UEs 115. In this
way, a UE 115 may further achieve power savings by skipping ON
durations if the UE 115 is not explicitly instructed to wake up by
the base station 105.
[0124] FIG. 4 illustrates an example of a power level timeline 400
for a UE 115 that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure. The power level
timeline 400 may correspond to approximate or relative power levels
for different modes of operation at a UE 115, such as a UE 115
described with reference to FIGS. 1 through 3. The UE 115 may
support additional power savings by implementing extended sleep
functionality (e.g., as compared to the UE operating timeline 300
illustrated in FIG. 3). By supporting wakeup procedures based on
wakeup signaling that may be received at a lower power level than
PDCCH signaling (e.g., using a lower power receiver than the
receiver used to receive the PDCCH signaling), the UE 115 may
efficiently determine whether to wake up for data and control
channel processing 445. As illustrated in FIG. 4, the height of
each bar may indicate a relative power level for a UE 115
performing the corresponding operation, where a higher bar
indicates a higher power level. For example, wakeup signal
reception 405 may correspond to a slightly higher power level than
a deep sleep 410 mode, but a lower power level than PDCCH-only
reception 440 or data and control channel processing 445.
[0125] A UE 115 may turn on a wakeup subsystem for wakeup signal
decoding while in a low power mode. This wakeup subsystem may be an
example of a low complexity receiver, such as a simple correlator.
As such, the wakeup subsystem may detect wakeup signals using a
lower power than a receiver (i.e., a standard or "full-power"
receiver) performing PDCCH decoding in an active mode. In some
cases, a wakeup signal may be a special type of waveform, such as
an on-off keying (OOK)-based tone, a preamble, a reference signal,
etc. The UE 115 may perform wakeup signal reception 405 prior to a
C-DRX ON duration 420. A pre-wakeup offset 415 may define a buffer
period between the wakeup signal reception 405 and the ON duration
420 (e.g., for the UE 115 to process any received wakeup signal and
perform a power ramp-up procedure 435). If the UE 115 does not
detect a wakeup signal during wakeup signal reception 405 (e.g., if
there is no downlink grant transmitted for the UE 115 at wakeup
signal reception 405-a during the pre-wakeup offset 415-a), the UE
115 may skip an ON duration 420 (e.g., ON duration 420-a) and
instead return to a deep sleep 410 mode until a next wakeup signal
reception 415 opportunity. This wakeup signal reception 405
supporting extended deep sleep 410 durations may save power at the
UE 115 by reducing the amount of PDCCH monitoring.
[0126] In some cases, the UE 115 may detect a wakeup signal during
wakeup signal reception. Based on this wakeup signal detection 425,
the UE 115 may perform a power ramp-up procedure 435 (e.g., during
a pre-wakeup offset 415-b). This power ramp-up procedure 435 may
transition the UE 115 from a first power level (e.g., a power level
associated with a deep sleep 410 mode) to a second power level
(e.g., a power level associated with a PDCCH-only reception 440
mode). The UE 115 may monitor for a grant 430 in the PDCCH-only
reception 440 mode during an ON duration 420-b. This grant may be
an example of a PDCCH grant scheduling data transmission or
reception for the UE 115, and the grant may be indicated by the
detected wakeup signal. For example, a base station 105 may
transmit a wakeup signal to the UE 115 to indicate that the base
station 105 is scheduled to transmit a PDCCH grant to the UE 115
during a next ON duration 420-b. The UE 115 may utilize a full
modem for PDCCH reception and decoding, rather than the wakeup
subsystem. For example, the UE 115 may wake up for the ON duration
420-b and may monitor for the PDCCH grant 430 using the full modem
at a power level greater than the power level used for wakeup
signal reception 405. Based on the received PDCCH grant 430, the UE
115 may determine a schedule for performing data and control
channel processing 445, which may be performed at a different power
level than the PDCCH-only reception 440. Following the data and
control channel processing 445, the UE 115 may remain in an active
mode and monitor for any further PDCCH signals. If the UE 115 does
not receive a further PDCCH grant before an inactivity timer
expires (e.g., the UE 115 is inactive for a certain threshold
duration 450), the UE 115 may perform a power ramp-down procedure
455 to return to a deep sleep 410. The UE 115 may then periodically
or aperiodically check for wakeup signals according to a DRX cycle
460. For example, wakeup signal reception 405 may occur near the
end of a DRX cycle 460 such that the UE 115 may wake up for a next
DRX cycle 460 if a wakeup signal is received.
[0127] The UE 115 may be configured with specific wakeup signaling
resource occasions and parameters. Using these parameters, a UE 115
may identify whether a wakeup signal is for that UE 115, and may
not wake up based on wakeup signals intended for other UEs 115. A
base station 105 transmitting wakeup signals may differentiate
between UEs 115 or groups of UEs 115 using these configuration
parameters. In this way, a base station 105 may wake up a large
number of UEs 115 within a same time window (e.g., a same wakeup
signal reception 405 period) using the different wakeup
configurations, supporting large amounts of data traffic in a
system. Moreover, the different UE wakeup signaling configurations
allows UEs 115 to remain asleep even when detecting wakeup signals
for other UEs 115 (e.g., wakeup signals transmitted according to
other configurations). In this way, even in systems with high
levels of data traffic, UEs 115 may achieve significant power
savings by remaining in deep sleep 410 mode until specifically
indicated to wake up by a base station 105.
[0128] FIG. 5 illustrates an example of a wakeup procedure timeline
500 for a wireless communications system that supports wakeup
signaling resource occasions in accordance with aspects of the
present disclosure. The wakeup procedure timeline 500 may
correspond to wakeup signaling between base station 105-b and UE
115-c, which may be examples of the corresponding devices described
with respect to FIGS. 1 through 4. Base station 105-b and UE 115-c
may operate within a wireless communications system supporting
beamforming, such as an mmW system. In some cases, UE 115-c may use
a low power receiver for detecting wakeup signals transmitted by
base station 105-b. Based on whether a wakeup signal is detected,
UE 115-c may either return to a lower power mode (i.e., go back to
sleep) or may transition to a higher power mode (i.e., wake up) to
receive and/or transmit data.
[0129] A C-DRX timeline 505 illustrates the operations performed by
UE 115-c. For example, during a first C-DRX ON duration 510-a
corresponding to a first C-DRX cycle 515-a, UE 115-c may receive
data from base station 105-b, transmit data to base station 105-b,
perform other communication operations in an active mode, or any
combination of these operations. Following the first C-DRX ON
duration 510-a, UE 115-c may enter a low power mode (e.g., based on
an inactivity timer). However, according to the C-DRX cycle 515
schedule, UE 115-c may periodically or aperiodically pre-wake up
for wakeup signal detection 520-a. In some cases, a pre-wakeup
procedure may involve UE 115-c transitioning to a higher power
level than the sleep mode but a lower power level than the active
mode to monitor for wakeup signals from base station 105-b.
[0130] In a first example, base station 105-b may not have data to
transmit to UE 115-c or receive from UE 115-c. In this example, at
525, base station 105-b may not transmit a wakeup signal to UE
115-c. In some cases, base station 105-b may instead transmit one
or more wakeup signals to other UEs 115 serviced by the base
station 105-b. UE 115-c may monitor for wakeup signals using a set
of downlink receive beams 530-a. If UE 115-c does not detect or
otherwise receive a wakeup signal intended for UE 115-c on any of
the downlink receive beams 530-a, the UE 115-c may skip a C-DRX ON
duration at 535 for a C-DRX cycle 515-b and instead may return to
the lower power mode (i.e., go back to sleep). In this way, UE
115-c may reduce its power consumption by not entering a C-DRX ON
duration 510 when there is no data scheduled for reception or
transmission.
[0131] In a second example, base station 105-b may identify data to
transmit to UE 115-c or data to receive from UE 115-c. In this
example, at 540, base station 105-b may transmit a wakeup signal to
UE 115-c using a beam sweeping procedure (e.g., transmitting the
wakeup signal using a number of downlink transmit beams). UE 115-c
may pre-wake up for wakeup signal detection 520-b during C-DRX
cycle 515-b and may attempt to detect the wakeup signal using a set
of downlink receive beams 530-b, which may be the same or different
from the set of downlink receive beams 530-a. If UE 115-c detects
the wakeup signal on any of these downlink receive beams 530-b, the
UE 115-c may perform a full wakeup procedure to transmit or receive
the scheduled data in a C-DRX ON duration 510-b.
[0132] The downlink transmit beams, downlink receive beams, or both
may be configured for improved detection at UE 115-c. For example,
base station 105-b may use a set of N.sub.Tx beams (e.g., out of up
to sixty-four synchronization signal block (SSB) beams) for wakeup
signal transmission and UE 115-c may use a set of N.sub.Rx beams
(e.g., out of up to sixty-four SSB beams) for wakeup signal
reception. The numbers of beams, the directions of the beams, or
both may be pre-configured for each wireless device or may be
configured based on a configuration message or configuration
function. For example, a configuration function for the beams may
be based on a link quality, UE mobility, one or more UE
capabilities, a C-DRX cycle 515 length, or some combination of
these or other relevant parameters for wakeup signal reception. In
some cases, the number and direction of downlink transmit beams,
downlink receive beams, or both may be determined by base station
105-b for each UE 115 or group of UEs 115. Base station 105-b may
use the determined number and direction of downlink transmit beams
for a wakeup signal beam sweeping procedure. Additionally or
alternatively, base station 105-b may transmit a configuration
message to UE 115-c to indicate the determined number and direction
of downlink receive beams for wakeup signal reception. In some
cases, UE 115-c may not maintain beam information during OFF
durations and may be pre-configured with default downlink receive
beams to use during pre-wake up for wakeup signal detection
520.
[0133] In some cases, UE 115-c may be configured with other wakeup
signal reception parameters. For example, these parameters may
include values defining the pre-wake up for wakeup signal detection
520 time period, such as a starting symbol for the time period, a
number of symbols corresponding to the duration of the time period,
or other time resources. In other cases, the parameters may include
decoding information for UE 115-c, such as a scrambling sequence, a
DCI format, an RNTI value, a decoding hypothesis, or some
combination of these. In some cases, the parameters indicated to UE
115-c may be based on a format of the wakeup signal. For example,
PDCCH-type wakeup signals and reference signal-type wakeup signals
may correspond to different sets of parameters. In some cases, base
station 105-b may configured UE 115-c with wakeup signal reception
parameters. UE 115-c may detect the wakeup signals intended for UE
115-c based on this wakeup signal monitoring configuration.
[0134] FIG. 6 illustrates a first example of a configuration for
wakeup signal resources 600 that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure. The
configuration for wakeup signal resources 600 may correspond to a
downlink control channel resource configuration, such as a
PDCCH-type wakeup signal configuration. A base station 105 may use
the configuration for wakeup signal resources 600 for
differentiating wakeup signals between UEs 115 or groups of UEs
115. This base station 105 and these UEs 115 may be examples of the
corresponding wireless devices described with reference to FIGS. 1
through 5. While the configuration for wakeup signal resources 600,
as illustrated, shows one possible wakeup signal resource
configuration, many other configurations are possible using any of
the techniques described herein.
[0135] UEs 115 within a wireless communications system may monitor
for wakeup signals in one or more wakeup signaling resource
occasions according to configurations of the UEs 115. For example,
a base station 105 may configure a UE 115 with a set of wakeup
signal resource configurations. In some cases, the UE 115 may store
the set of wakeup signal resource configurations in a lookup table
in memory. The base station 105 may then transmit a configuration
indicator to the UE 115 that indicates a specific wakeup signal
resource configuration for the UE 115 to use for wakeup signal
monitoring and reception. In another example, base station 105 may
store the set of wakeup signal resource configurations in memory
and may transmit an indication of one of the configurations to the
UE 115.
[0136] Each wakeup signal resource configuration may include a set
of configuration parameters. These configuration parameters may
include time resources, frequency resources, a DCI format, a
scrambling sequence, an RNTI, or any combination of these or other
relevant configuration parameters for differentiating wakeup
signals. Configuration parameters indicating time resource,
frequency resources, or both may indicate to a UE 115 how to
monitor for a wakeup signal transmitted to the UE 115.
Configuration parameters indicating a DCI format, a scrambling
sequence, or an RNTI may indicate to the UE 115 how to decode a
wakeup signal transmitted to the UE 115. For example, if the UE 115
successfully decodes a wakeup signal according to the configured
DCI format (e.g., if the decoded wakeup signal passes an error
detection check (EDC), such as a CRC), the UE 115 may determine
that the wakeup signal is intended for the UE 115. Similarly, if
the UE 115 performs a descrambling process for a received wakeup
signal according to the indicated scrambling sequence, the
indicated RNTI, or both, and successfully decodes the wakeup signal
based on this descrambling process, the UE 115 may use the received
wakeup signal to initiate a wakeup procedure.
[0137] In one specific example, a base station 105 may store a
wakeup signal resource configuration lookup table including time
resources for different UEs 115 or sets of UEs 115:
TABLE-US-00001 TABLE 1 An Example of a Wakeup Signal Resource
Configuration Lookup Table Starting Number of UE Symbol PDCCH
Symbols 1 0 2 2 2 3 3 5 3 4 9 1 5 11 2
[0138] The wakeup signal resource configuration lookup table may
support UE 115 multiplexing within a one slot wakeup window, where
the table indicates a starting symbol index 610 and a number of
symbols that each UE 115 or group of UEs 115 may monitor for wakeup
signal transmissions. For example, if the base station 105
configures a UE 115 with the configured resources for UE 1 (or UE
group 1) as defined in Table 1, the UE 115 may monitor for wakeup
signals using a low power receiver during symbol indices 0 and 1 of
a TTI or sTTI (e.g., a slot 605, where the slot 605 may correspond
to a wakeup signal reception period or pre-wakeup period for wakeup
signal detection as described with reference to FIGS. 4 and 5).
Similarly, a UE 115 configured for the dedicated wakeup signal
occasion defined for UE 2 may monitor for wakeup signals during
symbol indices 2, 3, and 4 of the slot 605, a UE 115 configured for
the dedicated wakeup signal occasion for UE 3 may monitor during
symbol indices 5, 6, and 7, a UE 115 configured for the dedicated
wakeup signal occasion for UE 4 may monitor during symbol index 9,
and a UE 115 configured for the dedicated wakeup signal occasion
for UE 5 may monitor during symbol indices 11 and 12 according to
the stored lookup table. In this way, the base station 105 may
transmit wakeup signals to any of five different UEs 115 or groups
of UEs 115 within a same slot 605, and each UE 115 may detect
whether one of the wakeup signals initiates a wakeup procedure for
that UE 115. Additionally or alternatively, a UE 115 may be
configured with multiple dedicated wakeup signal occasions. For
example, a UE 115 may be configured for the dedicated wakeup signal
occasions defined for UEs 1 and 3, where the UE 115 may monitor for
wakeup transmissions during a first monitoring occasion spanning
symbol indices 0 to 1 and a second monitoring occasion spanning
symbol indices 5 to 7.
[0139] In some cases, a UE 115 may be configured with a time and/or
frequency resource configuration parameter for wakeup signal
monitoring. For example, a frequency resource configuration
parameter may specify a CORESET configuration (e.g., one or more
CORESETs for a particular BWP) for the UE 115 to perform wakeup
signal detection. Additionally or alternatively, a time resource
configuration parameter may specify a search space configuration
(e.g., a slot 610 periodicity and an offset in TTIs for one or more
search spaces from some reference time) and one or more monitoring
occasions within the slot 610. The UE 115 may activate a low power
receiver during the times specified by the configuration and
monitor for wakeup signals on the frequencies specified by the
configuration.
[0140] In one example, two UEs 115 or groups of UEs 115 may share
the same time and frequency resources for wakeup signal monitoring
(e.g., according to a configuration of the wakeup signal
resources). In this example, the wakeup signals transmitted by the
base station 105 for the different UEs 115 or groups of UEs 115 may
use different DCI-formats, scrambling sequences, RNTI values, or
some combination of these to differentiate the wakeup signals, such
that each UE 115 or group of UEs 115 may successfully identify
whether a detected wakeup signal was intended for that UE 115 or
group of UEs 115. For example, a UE 115 may decode a received
wakeup signal using a DCI-format, a scrambling sequence, an RNTI
value, or some combination of these configured for that UE 115. If
the decoding process is successful, the UE 115 may determine that
the received wakeup signal was intended for it, and the UE 115 may
initiate a wakeup procedure. If the decoding process is
unsuccessful using the configured decoding parameters, the UE 115
may determine that the received wakeup signal was intended for a
different UE 115 or group of UEs 115 and may return to a sleep
mode.
[0141] When a UE 115 detects a wakeup signal transmitted according
to the wakeup resource configuration for the UE 115, the UE 115 may
initiate a wakeup procedure (e.g., transitioning from a lower power
mode to a higher power mode in order to support PDCCH reception and
data communication). This higher power mode may correspond to an
active duration for the UE 115. The UE 115 may operate according to
different configurations pre-wakeup and post-wakeup. For example,
the UE 115 may monitor for and receive PDCCH-type wakeup signals
according to a first configuration of wakeup signaling resources
(e.g., a first search space configuration for monitoring a downlink
control channel). However, after the UE 115 wakes up (i.e., during
the active duration), the UE 115 may monitor for and receive PDCCH
transmissions scheduling the UE 115 for data communication
according to a second configuration (e.g., a different PDCCH
configuration, such as a second search space configuration for
monitoring the downlink control channel). In some cases, this
second configuration may correspond to a control channel resource
configuration associated with a serving cell configuration (e.g., a
ServingCellConfig) for the UE 115. For example, a UE 115 may be
configured to receive PDCCH-type wakeup signals within any symbol
indices 610 of a slot 605 based on the configuration for wakeup
signal resources 600, while the UE 115 may be limited to receiving
PDCCH scheduling within the first three symbols of a slot based on
an active mode configuration of the UE 115.
[0142] FIG. 7 illustrates a second example of a configuration for
wakeup signal resources 700 that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure. The
configuration for wakeup signal resources 700 may correspond to a
reference signal configuration. A base station 105 may use the
configuration for wakeup signal resources 700 for differentiating
wakeup signals between UEs 115 or groups of UEs 115. This base
station 105 and these UEs 115 may be examples of the corresponding
wireless devices described with reference to FIGS. 1 through 6.
While the configuration for wakeup signal resources 700, as
illustrated, shows one possible wakeup signal resource
configuration, many other configurations are possible using any of
the techniques described herein.
[0143] UEs 115 within a wireless communications system (e.g., an
mmW system) may monitor for wakeup signals in one or more wakeup
signaling resource occasions according configurations of the UEs
115. For example, a base station 105 may configure a UE 115 with a
set of wakeup signal resource configurations. In some cases, the UE
115 may store the set of wakeup signal resource configurations in a
lookup table in memory. The base station 105 may then transmit a
configuration indicator to the UE 115 that indicates a specific
wakeup signal resource configuration for the UE 115 to use for
wakeup signal monitoring and reception. In another example, base
station 105 may store the set of wakeup signal resource
configurations in memory and may transmit an indication of one of
the configurations to the UE 115. Each wakeup signal resource
configuration may include a set of configuration parameters. These
configuration parameters may include time resources, frequency
resources, a number of beams for a beam sweep procedure, a number
of repetitions per beam for the beam sweep procedure, beam
directions, one or more beam patterns, a scrambling sequence, a
decoding hypothesis, or any combination of these or other relevant
configuration parameters for differentiating reference signal-type
wakeup signals.
[0144] In some cases, a UE 115 may be configured with a time and/or
frequency resource configuration parameter for wakeup signal
monitoring. This resource configuration may be an example of a
reference signal resource configuration (e.g., similar to a CSI-RS
configuration) for receiving reference signal-type wakeup signals.
This reference signal resource configuration may apply to
monitoring for reference signals for initiating a wakeup procedure,
but may not apply to monitoring for reference signals after the UE
115 is awake (i.e., is operating in an active mode). For example,
when monitoring for wakeup signals in a low power mode, a UE 115
may monitor according to the configuration for wakeup signal
resources 700. When monitoring for references signals (e.g.,
CSI-RSs, TRSs, DMRSs, etc.) in a high power mode (e.g., during an
active duration), the UE 115 may monitor according to a serving
cell configuration for the UE 115.
[0145] As illustrated, a base station 105 may configure four
different UEs 115 or UE 115 groups with different configurations of
wakeup signal resources. The base station 105 may multiplex these
four UEs 115 or groups of UEs 115 within a same wakeup window
spanning a same TTI (e.g., a slot 710) and bandwidth (e.g.,
resource blocks (RBs) 715). Each of the UEs 115 or groups of UEs
115 may be configured with a different number of beams 705,
different repetition factors for the beams 705, different beam
patterns, or some combination of these configuration
parameters.
[0146] For example, a first UE 115 may be configured with four
beams 705 (e.g., beams 705-a, 705-b, 705-c, and 705-d), where each
beam 705 is not repeated in the beam sweep procedure. These beams
705 may correspond to downlink transmit beams--where the UE 115
attempts to receive a wakeup signal according to the configured
downlink transmit beams--or downlink receive beams for the UE 115
to use for wakeup signal reception in the configured time and
frequency resources. For example, the first UE 115 may be
configured with four beams 705 within a TTI (e.g., the slot 710),
where each beam has a repetition factor of 1 (e.g., each beam 705
is used in a single symbol of the TTI). Across time, the set of
four beams 705 may be configured with a beam pattern of beam 705-a,
then beam 705-b, then beam 705-d, and then beam 705-c. This same
beam pattern may be repeated at multiple different frequencies
within the set of RBs 715. A second UE 115 may be configured with
the same number of beams 705, the same beam repetitions, and the
same beam pattern, but in different frequency resources. A third UE
115 may be configured with two beams 705 (e.g., beams 705-a and
705-d), where each of the two beams 705 is repeated once in the
beam sweep procedure (e.g., beam 705-a and beam 705-d each have a
repetition factor of 2 according to the wakeup signal resource
configuration). A fourth UE 115 may be configured with one beam
705-c, where the beam 705-c is repeated such that the wakeup signal
is transmitted on that beam 705-c across four symbols of the slot
710 (e.g., the beam 705-c may be configured with a repetition
factor of 4).
[0147] In some cases, a UE 115 may determine to initiate a wakeup
procedure based on receiving a wakeup signal on any of the
configured beams 705 in the configured resources. For example, the
UE 115 may be configured with a particular decoding hypothesis for
successfully decoding a received wakeup signal according to the
wakeup signal resource configuration for the UE 115. This decoding
hypothesis may correspond to a beam pattern for receiving the
wakeup signal from the base station 105. If the UE 115 receives a
wakeup signal according to the configured beam pattern, the UE 115
may successfully decode the wakeup signal using the configured
decoding hypothesis and, correspondingly, may initiate a wakeup
procedure. It is to be understood that these UE 115 configurations
are given as examples, and many other UE 115 configurations for
reference signal-type wakeup signal reception are possible using
the techniques described herein.
[0148] FIG. 8 illustrates an example of a process flow 800 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The process flow 800 may include
base station 105-c and UE 115-d, which may be examples of the
corresponding devices described with reference to FIGS. 1 through
7. UE 115-d may support C-DRX operations using wakeup signals to
achieve power savings. UE 115-d may be configured (e.g.,
pre-configured or configured by base station 105-c) to receive
wakeup signals in specific wakeup signal resources to efficiently
utilize the available resources in the system. Alternative examples
of the following may be implemented, where some steps are performed
in a different order than described or are not performed at all. In
some cases, steps may include additional features not mentioned
below, or further steps may be added.
[0149] At 805, base station 105-c may transmit configuration
signaling to UE 115-d. The configuration signaling may configure UE
115-d with a set of wakeup signal resource configurations.
Additionally or alternatively, the configuration signaling may
configure UE 115-d with a monitoring configuration when operating
in an active mode. In some cases, the UE 115-d may generate a table
based on the configuration signaling, and each index in the table
may correspond to a respective configuration (e.g., a respective
wakeup signal resource configuration). Each wakeup signal resource
configuration may include a set of one or more resource parameters.
At 810, base station 105-c may transmit a configuration indicator
to UE 115-d indicating a first wakeup signal resource configuration
of the set of wakeup signal resource configurations. For example,
the UE 115-d may index the configured table using the received
configuration indicator. UE 115-d may determine one or more
resource parameters for monitoring for wakeup signals based on the
indicated first wakeup signal resource configuration.
[0150] In some cases, the first wakeup signal resource
configuration may be an example of a downlink control channel
resource configuration (e.g., a PDCCH configuration). The first
wakeup signal resource configuration may correspond to resource
parameters indicating a starting symbol within a TTI, a number of
symbols within the TTI, a frequency resource (e.g., a CORESET), a
time resource (e.g., a search space), a scrambling sequence, a DCI
format, an RNTI value, or some combination of these. In other
cases, the first wakeup signal resource configuration may be an
example of a reference signal configuration. The first wakeup
signal resource configuration may indicate a number of different
beams by which a wakeup signal is transmitted, a beam repetition
factor for at least one of the beams, a beam pattern for at least
one of the beams, a beam pattern for a set of different beams, a
decoding hypothesis for decoding the wakeup signal, or some
combination of these.
[0151] At 815, UE 115-d may operate according to a low power mode.
For example, the UE 115-d may be "asleep," and may not transmit or
receive data in this low power mode. UE 115-d may periodically
monitor for wakeup signals to identify if the UE 115-d should wake
up for data communication. For example, at 820, UE 115-d may
monitor a wakeup signal resource for a wakeup signal transmission
based on the first wakeup signal resource configuration.
[0152] In some cases, base station 105-c may not identify any data
for communication with UE 115-d. Accordingly, base station 105-c
may not transmit a wakeup signal to UE 115-d during the configured
wakeup signal monitoring occasion. If UE 115-d does not detect a
wakeup signal, UE 115-d may remain in the low power mode. However,
in other cases, base station 105-c may identify data for
communication with UE 115-d. In these cases, base station 105-c may
transmit a wakeup signal to UE 115-d at 825. Base station 105-d may
transmit the wakeup signal using the wakeup signal resource that UE
115-d is configured to monitor. UE 115-d may detect the wakeup
signal based on the monitoring procedure and may identify that the
wakeup signal is intended for UE 115-d. Accordingly, UE 115-d may
initiate a wakeup procedure at 830 based on detecting the wakeup
signal. In some examples, the wakeup signal may be an example of an
OOK-based tone, a preamble, a reference signal, a PDCCH
transmission, or some combination of these signals.
[0153] Based on the wakeup procedure, UE 115-d may transition from
the low power mode to a high power mode (e.g., where "high" and
"low" are relative to each other). In the high power mode during an
ON duration, UE 115-d may monitor a control channel (e.g., the
PDCCH) for a scheduling grant at 835. At 840, base station 105-c
may transmit a scheduling grant to UE 115-d on the PDCCH, where the
grant schedules UE 115-d for data transmission, data reception, or
both during an active duration. At 845, UE 115-d and base station
105-c may communicate according to the scheduling grant.
[0154] In some cases, UE 115-d may use an inactivity timer to
determine when to return to the low power mode. For example, after
UE 115-d has stopped communicating with base station 105-c, UE
115-d may initiate the inactivity timer. If the timer expires
before UE 115-d is scheduled for any further transmissions by base
station 105-c (e.g., if UE 115-d has not received a grant from base
station 105-c within a defined amount of time), UE 115-d may
initiate a sleep procedure at 850 and return to the low power
mode.
[0155] FIG. 9 shows a block diagram 900 of a device 905 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The device 905 may be an example
of aspects of a UE 115 as described herein. The device 905 may
include a receiver 910, a wakeup signaling configuration module
915, and a transmitter 920. The device 905 may also include a
processor. Each of these components may be in communication with
one another (e.g., via one or more buses).
[0156] The receiver 910 may receive information such as packets,
user data, or control information associated with various
information channels (e.g., control channels, data channels, and
information related to wakeup signaling resource occasions, etc.).
Information may be passed on to other components of the device 905.
The receiver 910 may be an example of aspects of the transceiver
1220 described with reference to FIG. 12. The receiver 910 may
utilize a single antenna or a set of antennas.
[0157] The wakeup signaling configuration module 915 may be a
component of a UE 115. The wakeup signaling configuration module
915 may receive configuration signaling configuring the UE 115 with
a set of wakeup signal resource configurations, receive a
configuration indicator indicating a first wakeup signal resource
configuration of the set of wakeup signal resource configurations,
and monitor a wakeup signal resource for a wakeup signal
transmission based on the first wakeup signal resource
configuration. The wakeup signaling configuration module 915 may be
an example of aspects of the wakeup signaling configuration module
1210 described herein.
[0158] The wakeup signaling configuration module 915, or its
sub-components, may be implemented in hardware, code (e.g.,
software or firmware) executed by a processor, or any combination
thereof. If implemented in code executed by a processor, the
functions of the wakeup signaling configuration module 915, or its
sub-components may be executed by a general-purpose processor, a
digital signal processor (DSP), an application-specific integrated
circuit (ASIC), a field-programmable gate array (FPGA) or other
programmable logic device, discrete gate or transistor logic,
discrete hardware components, or any combination thereof designed
to perform the functions described in the present disclosure.
[0159] The wakeup signaling configuration module 915, or its
sub-components, may be physically located at various positions,
including being distributed such that portions of functions are
implemented at different physical locations by one or more physical
components. In some examples, the wakeup signaling configuration
module 915, or its sub-components, may be a separate and distinct
component in accordance with various aspects of the present
disclosure. In some examples, the wakeup signaling configuration
module 915, or its sub-components, may be combined with one or more
other hardware components, including but not limited to an
input/output (I/O) component, a transceiver, a network server,
another computing device, one or more other components described in
the present disclosure, or a combination thereof in accordance with
various aspects of the present disclosure.
[0160] The transmitter 920 may transmit signals generated by other
components of the device 905. In some examples, the transmitter 920
may be collocated with a receiver 910 in a transceiver module. For
example, the transmitter 920 may be an example of aspects of the
transceiver 1220 described with reference to FIG. 12. The
transmitter 920 may utilize a single antenna or a set of
antennas.
[0161] FIG. 10 shows a block diagram 1000 of a device 1005 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The device 1005 may be an
example of aspects of a device 905, or a UE 115 as described
herein. The device 1005 may include a receiver 1010, a wakeup
signaling configuration module 1015, and a transmitter 1035. The
device 1005 may also include a processor. Each of these components
may be in communication with one another (e.g., via one or more
buses).
[0162] The receiver 1010 may receive information such as packets,
user data, or control information associated with various
information channels (e.g., control channels, data channels, and
information related to wakeup signaling resource occasions, etc.).
Information may be passed on to other components of the device
1005. The receiver 1010 may be an example of aspects of the
transceiver 1220 described with reference to FIG. 12. The receiver
1010 may utilize a single antenna or a set of antennas.
[0163] The wakeup signaling configuration module 1015 may be an
example of aspects of the wakeup signaling configuration module 915
as described herein. The wakeup signaling configuration module 1015
may include a configuration signaling component 1020, a
configuration identifier 1025, and a monitoring component 1030. The
wakeup signaling configuration module 1015 may be an example of
aspects of the wakeup signaling configuration module 1210 described
herein.
[0164] The configuration signaling component 1020 may be an example
of a component of a UE 115. The configuration signaling component
1020 may receive configuration signaling configuring the UE 115
with a set of wakeup signal resource configurations. The
configuration identifier 1025 may receive a configuration indicator
indicating a first wakeup signal resource configuration of the set
of wakeup signal resource configurations. The monitoring component
1030 may monitor a wakeup signal resource for a wakeup signal
transmission based on the first wakeup signal resource
configuration.
[0165] The transmitter 1035 may transmit signals generated by other
components of the device 1005. In some examples, the transmitter
1035 may be collocated with a receiver 1010 in a transceiver
module. For example, the transmitter 1035 may be an example of
aspects of the transceiver 1220 described with reference to FIG.
12. The transmitter 1035 may utilize a single antenna or a set of
antennas.
[0166] FIG. 11 shows a block diagram 1100 of a wakeup signaling
configuration module 1105 that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure. The
wakeup signaling configuration module 1105 may be an example of
aspects of a wakeup signaling configuration module 915, a wakeup
signaling configuration module 1015, or a wakeup signaling
configuration module 1210 described herein. The wakeup signaling
configuration module 1105 may include a configuration signaling
component 1110, a configuration identifier 1115, a monitoring
component 1120, an indexing component 1125, a decoding component
1130, a wakeup signal detection component 1135, a wakeup initiation
component 1140, a scheduling component 1145, a sleep initiation
component 1150, and a control channel configuration identifier
1155. Each of these modules may communicate, directly or
indirectly, with one another (e.g., via one or more buses).
[0167] The configuration signaling component 1110 may receive
configuration signaling configuring the UE with a set of wakeup
signal resource configurations. The configuration identifier 1115
may receive a configuration indicator indicating a first wakeup
signal resource configuration of the set of wakeup signal resource
configurations. In some cases, the first wakeup signal resource
configuration is a downlink control channel resource configuration.
In other cases, the first wakeup signal configuration is a
reference signal configuration.
[0168] The monitoring component 1120 may monitor a wakeup signal
resource for a wakeup signal transmission based on the first wakeup
signal resource configuration.
[0169] The indexing component 1125 may index a table, based on the
configuration indicator, for identifying at least one resource
configuration parameter of the first wakeup signal resource
configuration, where monitoring the wakeup signal resource further
includes the monitoring component 1120 monitoring the wakeup signal
resource for the wakeup signal transmission based on the at least
one resource configuration parameter.
[0170] In some examples, at least one resource configuration
parameter indicates a starting symbol within a transmission time
interval, and the monitoring component 1120 may monitor the wakeup
signal resource for the wakeup signal transmission beginning at the
starting symbol within the transmission time interval. In some
examples, at least one resource configuration parameter indicates a
number of symbols within a transmission time interval, and the
monitoring component 1120 may monitor the wakeup signal resource
for the wakeup signal transmission beginning within the
transmission time interval at the starting symbol and continuing
for the number of symbols.
[0171] In some examples, at least one resource configuration
parameter is a frequency resource configuration parameter, a time
resource configuration parameter, or both, and the monitoring
component 1120 may monitor the wakeup signal resource for the
wakeup signal transmission based on the frequency resource
configuration parameter, the time resource configuration parameter,
or both. In some cases, the at least one resource configuration
parameter is the frequency resource configuration parameter, and
the frequency resource configuration parameter is a control
resource set configuration parameter. In other cases, the at least
one resource configuration parameter is the time resource
configuration parameter, where the time resource configuration
parameter indicates a search space configuration and a control
channel monitoring occasion within a transmission time interval. In
some cases, the search space configuration indicates a transmission
time interval periodicity and an offset indicating a number of
transmission time intervals relative to a reference time.
[0172] In some examples, the first wakeup signal resource
configuration indicates a number of different beams by which a
wakeup signal is transmitted within a transmission time interval,
and the monitoring component 1120 may monitor the wakeup signal
resource for the wakeup signal transmission within the transmission
time interval based on the number of different beams.
[0173] In some examples, the first wakeup signal resource
configuration indicates a beam repetition factor for at least one
beam by which a wakeup signal is transmitted within a transmission
time interval, and the monitoring component 1120 may monitor the
wakeup signal resource for the wakeup signal transmission within
the transmission time interval based on the beam repetition
factor.
[0174] In some examples, the first wakeup signal resource
configuration indicates a beam pattern for at least one beam by
which a wakeup signal is transmitted within a transmission time
interval, and the monitoring component 1120 may monitor the wakeup
signal resource for the wakeup signal transmission within the
transmission time interval based on the beam pattern. Additionally
or alternatively, the first wakeup signal resource configuration
indicates a beam pattern for a set of different beams by which a
wakeup signal is transmitted within a transmission time interval,
and the monitoring component 1120 may monitor the wakeup signal
resource for the wakeup signal transmission within the transmission
time interval based on the beam pattern.
[0175] In some examples, the monitoring component 1120 may monitor
a downlink control channel for the wakeup signal transmission.
[0176] In some examples, at least one resource configuration
parameter indicates a scrambling sequence, and the decoding
component 1130 may decode the first wakeup signal resource based on
the scrambling sequence. In some examples, at least one resource
configuration parameter indicates a DCI format, and the decoding
component 1130 may decode the first wakeup signal resource based on
the DCI format. In some examples, at least one resource
configuration parameter indicates an RNTI, and the decoding
component 1130 may decode the first wakeup signal resource based on
the RNTI.
[0177] In some examples, each wakeup signal resource configuration
of the set of wakeup signal resource configurations corresponds to
a different decoding hypothesis of a set of decoding hypotheses,
and the decoding component 1130 may identify a first decoding
hypothesis of the set of decoding hypotheses based on the first
wakeup signal configuration and may monitor the wakeup signal
resource for the wakeup signal transmission based on the first
decoding hypothesis. In some cases, each decoding hypothesis of the
set of decoding hypotheses corresponds to a different beam pattern
for at least one beam by which a wakeup signal is transmitted
within a transmission time interval.
[0178] The wakeup signal detection component 1135 may detect a
wakeup signal for the UE within the wakeup signal resource. The
wakeup initiation component 1140 may initiate a wakeup procedure
based on detecting the wakeup signal and may monitor a control
channel subsequent to initiating the wakeup procedure.
[0179] The scheduling component 1145 may detect, within the control
channel, a grant from a serving base station. In some examples, the
scheduling component 1145 may communicate based on the grant. The
sleep initiation component 1150 may initiate a sleep procedure
based on determining that a grant has not been received within a
defined amount of time.
[0180] The control channel configuration identifier 1155 may
identify a control channel resource configuration of a serving base
station. In some examples, the control channel configuration
identifier 1155 may monitor the control channel based on the
control channel resource configuration. In some cases, the control
channel resource configuration differs from the first wakeup signal
resource configuration.
[0181] A UE may implement the wakeup signaling configuration module
1105. In some cases, the configuration signaling component 1110 may
receive a first search space configuration for monitoring a
downlink control channel while operating in a low power mode and
may receive a second search space configuration for monitoring the
downlink control channel while operating in an active mode, where
the second search space configuration is different from the first
search space configuration. The monitoring component 1120 may
monitor the downlink control channel according to the first search
space configuration for a wakeup signal transmission based on the
UE operating in the low power mode.
[0182] In some cases, the first search space configuration includes
at least one resource configuration parameter and the monitoring
the downlink control channel is based on the at least one resource
configuration parameter. For example, the at least one resource
configuration parameter may be a starting symbol within a TTI, a
number of symbols within the TTI, a frequency resource
configuration parameter (e.g., a CORESET configuration parameter),
a time resource configuration parameter (e.g., a search space
configuration parameter or control channel monitoring occasion
configuration parameter), a scrambling sequence, a DCI format, an
RNTI, or a combination thereof, and monitoring the downlink control
channel, decoding the wakeup signal transmission, or both may be
based on any number of these parameters. In some examples, the
first search space configuration may include multiple CORESETs in a
BWP, multiple control channel monitoring occasions within a TTI or
search space, or both.
[0183] The wakeup signal detection component 1135 may detect a
wakeup signal for the UE based on monitoring the downlink control
channel according to the first search space configuration. The
wakeup initiation component 1140 may initiate a wakeup procedure
based on detecting the wakeup signal. The monitoring component 1120
may monitor the downlink control channel subsequent to initiating
the wakeup procedure according to the second search space
configuration based on the UE operating in the active mode. In some
cases, the decoding component 1130 may detect a grant from a
serving base station based on monitoring the downlink control
channel according to the second search space configuration and the
scheduling component 1145 may communicate with the serving base
station based on the grant. In some other cases, the sleep
initiation component 1150 may initiate a sleep procedure based on
determining that a grant has not been received within a defined
amount of time from monitoring the downlink control channel
according to the second search space configuration and the
monitoring component 1120 may monitor the downlink control channel
subsequent to initiating the sleep procedure according to the first
search space configuration based on the UE operating in the low
power mode. The UE may monitor the downlink control channel
according to the first search space configuration using a low power
receiver based on the UE operating in the low power mode and may
monitor the downlink control channel according to the second search
space configuration using a standard receiver different from the
low power receiver based on the UE operating in the active
mode.
[0184] FIG. 12 shows a diagram of a system 1200 including a device
1205 that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure. The device 1205
may be an example of or include the components of device 905,
device 1005, or a UE 115 as described herein. The device 1205 may
include components for bi-directional voice and data communications
including components for transmitting and receiving communications,
including a wakeup signaling configuration module 1210, an I/O
controller 1215, a transceiver 1220, an antenna 1225, memory 1230,
and a processor 1240. These components may be in electronic
communication via one or more buses (e.g., bus 1245).
[0185] The wakeup signaling configuration module 1210 may receive
configuration signaling configuring the device 1205 (e.g., a UE
115) with a set of wakeup signal resource configurations, receive a
configuration indicator indicating a first wakeup signal resource
configuration of the set of wakeup signal resource configurations,
and monitor a wakeup signal resource for a wakeup signal
transmission based on the first wakeup signal resource
configuration.
[0186] The I/O controller 1215 may manage input and output signals
for the device 1205. The I/O controller 1215 may also manage
peripherals not integrated into the device 1205. In some cases, the
I/O controller 1215 may represent a physical connection or port to
an external peripheral. In some cases, the I/O controller 1215 may
utilize an operating system such as iOS.RTM., ANDROID.RTM.,
MS-DOS.RTM., MS-WINDOWS.RTM., OS/2.RTM., UNIX.RTM., LINUX.RTM., or
another known operating system. In other cases, the I/O controller
1215 may represent or interact with a modem, a keyboard, a mouse, a
touchscreen, or a similar device. In some cases, the I/O controller
1215 may be implemented as part of a processor. In some cases, a
user may interact with the device 1205 via the I/O controller 1215
or via hardware components controlled by the I/O controller
1215.
[0187] The transceiver 1220 may communicate bi-directionally, via
one or more antennas, wired, or wireless links as described above.
For example, the transceiver 1220 may represent a wireless
transceiver and may communicate bi-directionally with another
wireless transceiver. The transceiver 1220 may also include a modem
to modulate the packets and provide the modulated packets to the
antennas for transmission, and to demodulate packets received from
the antennas.
[0188] In some cases, the wireless device may include a single
antenna 1225. However, in some cases the device may have more than
one antenna 1225, which may be capable of concurrently transmitting
or receiving multiple wireless transmissions.
[0189] The memory 1230 may include random-access memory (RAM) and
read-only memory (ROM). The memory 1230 may store
computer-readable, computer-executable code 1235 including
instructions that, when executed, cause the processor to perform
various functions described herein. In some cases, the memory 1230
may contain, among other things, a basic I/O system (BIOS) which
may control basic hardware or software operation such as the
interaction with peripheral components or devices.
[0190] The processor 1240 may include an intelligent hardware
device (e.g., a general-purpose processor, a DSP, a CPU, a
microcontroller, an ASIC, an FPGA, a programmable logic device, a
discrete gate or transistor logic component, a discrete hardware
component, or any combination thereof). In some cases, the
processor 1240 may be configured to operate a memory array using a
memory controller. In other cases, a memory controller may be
integrated into the processor 1240. The processor 1240 may be
configured to execute computer-readable instructions stored in a
memory (e.g., the memory 1230) to cause the device 1205 to perform
various functions (e.g., functions or tasks supporting wakeup
signaling resource occasions).
[0191] The code 1235 may include instructions to implement aspects
of the present disclosure, including instructions to support
wireless communications. The code 1235 may be stored in a
non-transitory computer-readable medium such as system memory or
other type of memory. In some cases, the code 1235 may not be
directly executable by the processor 1240 but may cause a computer
(e.g., when compiled and executed) to perform functions described
herein.
[0192] FIG. 13 shows a block diagram 1300 of a device 1305 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The device 1305 may be an
example of aspects of a base station 105 as described herein. The
device 1305 may include a receiver 1310, a wakeup signaling
configuration module 1315, and a transmitter 1320. The device 1305
may also include a processor. Each of these components may be in
communication with one another (e.g., via one or more buses).
[0193] The receiver 1310 may receive information such as packets,
user data, or control information associated with various
information channels (e.g., control channels, data channels, and
information related to wakeup signaling resource occasions, etc.).
Information may be passed on to other components of the device
1305. The receiver 1310 may be an example of aspects of the
transceiver 1620 described with reference to FIG. 16. The receiver
1310 may utilize a single antenna or a set of antennas.
[0194] The wakeup signaling configuration module 1315 may be a
component of a base station 105. The wakeup signaling configuration
module 1315 may transmit configuration signaling configuring a UE
115 with a set of wakeup signal resource configurations, transmit a
configuration indicator indicating a first wakeup signal resource
configuration of the set of wakeup signal resource configurations,
and transmit a wakeup signal transmission using a wakeup signal
resource based on the first wakeup signal resource configuration.
The wakeup signaling configuration module 1315 may be an example of
aspects of the wakeup signaling configuration module 1610 described
herein.
[0195] The wakeup signaling configuration module 1315, or its
sub-components, may be implemented in hardware, code (e.g.,
software or firmware) executed by a processor, or any combination
thereof. If implemented in code executed by a processor, the
functions of the wakeup signaling configuration module 1315, or its
sub-components may be executed by a general-purpose processor, a
DSP, an ASIC, an FPGA or other programmable logic device, discrete
gate or transistor logic, discrete hardware components, or any
combination thereof designed to perform the functions described in
the present disclosure.
[0196] The wakeup signaling configuration module 1315, or its
sub-components, may be physically located at various positions,
including being distributed such that portions of functions are
implemented at different physical locations by one or more physical
components. In some examples, the wakeup signaling configuration
module 1315, or its sub-components, may be a separate and distinct
component in accordance with various aspects of the present
disclosure. In some examples, the wakeup signaling configuration
module 1315, or its sub-components, may be combined with one or
more other hardware components, including but not limited to an I/O
component, a transceiver, a network server, another computing
device, one or more other components described in the present
disclosure, or a combination thereof in accordance with various
aspects of the present disclosure.
[0197] The transmitter 1320 may transmit signals generated by other
components of the device 1305. In some examples, the transmitter
1320 may be collocated with a receiver 1310 in a transceiver
module. For example, the transmitter 1320 may be an example of
aspects of the transceiver 1620 described with reference to FIG.
16. The transmitter 1320 may utilize a single antenna or a set of
antennas.
[0198] FIG. 14 shows a block diagram 1400 of a device 1405 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The device 1405 may be an
example of aspects of a device 1305, or a base station 105 as
described herein. The device 1405 may include a receiver 1410, a
wakeup signaling configuration module 1415, and a transmitter 1435.
The device 1405 may also include a processor. Each of these
components may be in communication with one another (e.g., via one
or more buses).
[0199] The receiver 1410 may receive information such as packets,
user data, or control information associated with various
information channels (e.g., control channels, data channels, and
information related to wakeup signaling resource occasions, etc.).
Information may be passed on to other components of the device
1405. The receiver 1410 may be an example of aspects of the
transceiver 1620 described with reference to FIG. 16. The receiver
1410 may utilize a single antenna or a set of antennas.
[0200] The wakeup signaling configuration module 1415 may be an
example of aspects of the wakeup signaling configuration module
1315 as described herein. The wakeup signaling configuration module
1415 may include a configuration signaling component 1420, a
configuration indicator 1425, and a wakeup signal transmission
component 1430. The wakeup signaling configuration module 1415 may
be an example of aspects of the wakeup signaling configuration
module 1610 described herein.
[0201] The configuration signaling component 1420 may transmit
configuration signaling configuring a UE 115 with a set of wakeup
signal resource configurations. The configuration indicator 1425
may transmit a configuration indicator indicating a first wakeup
signal resource configuration of the set of wakeup signal resource
configurations. The wakeup signal transmission component 1430 may
transmit a wakeup signal transmission using a wakeup signal
resource based on the first wakeup signal resource
configuration.
[0202] The transmitter 1435 may transmit signals generated by other
components of the device 1405. In some examples, the transmitter
1435 may be collocated with a receiver 1410 in a transceiver
module. For example, the transmitter 1435 may be an example of
aspects of the transceiver 1620 described with reference to FIG.
16. The transmitter 1435 may utilize a single antenna or a set of
antennas.
[0203] FIG. 15 shows a block diagram 1500 of a wakeup signaling
configuration module 1505 that supports wakeup signaling resource
occasions in accordance with aspects of the present disclosure. The
wakeup signaling configuration module 1505 may be an example of
aspects of a wakeup signaling configuration module 1315, a wakeup
signaling configuration module 1415, or a wakeup signaling
configuration module 1610 described herein. The wakeup signaling
configuration module 1505 may include a configuration signaling
component 1510, a configuration indicator 1515, a wakeup signal
transmission component 1520, and a decoding hypothesis component
1525. Each of these modules may communicate, directly or
indirectly, with one another (e.g., via one or more buses).
[0204] The configuration signaling component 1510 may transmit
configuration signaling configuring a UE 115 with a set of wakeup
signal resource configurations. In some cases, the configuration
signaling indicates a configuration of a table that includes at
least one resource configuration parameter for each wakeup signal
resource configuration of the set of wakeup signal resource
configurations.
[0205] The configuration indicator 1515 may transmit a
configuration indicator indicating a first wakeup signal resource
configuration of the set of wakeup signal resource configurations.
In some cases, the first wakeup signal resource configuration
indicates a DCI format, a scrambling sequence, an RNTI, or any
combination thereof. In some cases, the first wakeup signal
resource is a downlink control channel. In some cases, the first
wakeup signal resource configuration is a reference signal resource
configuration. In other cases, the first wakeup signal resource
configuration is a downlink control channel resource
configuration.
[0206] The wakeup signal transmission component 1520 may transmit a
wakeup signal transmission using a wakeup signal resource based on
the first wakeup signal resource configuration.
[0207] In some examples, the first wakeup signal resource
configuration indicates a starting symbol within a transmission
time interval, and the wakeup signal transmission component 1520
may transmit the wakeup signal transmission using the wakeup signal
resource beginning at the starting symbol within the transmission
time interval. In some examples, the first wakeup signal resource
configuration indicates a number of symbols within the transmission
time interval, and the wakeup signal transmission component 1520
may transmit the wakeup signal transmission using the wakeup signal
resource beginning within the transmission time interval at the
starting symbol and continuing for the number of symbols.
[0208] In some examples, the first wakeup signal resource
configuration indicates a frequency resource configuration
parameter, a time resource configuration parameter, or both, and
the wakeup signal transmission component 1520 may transmit the
wakeup signal transmission using the wakeup signal resource based
on the frequency resource configuration parameter, the time
resource configuration parameter, or both.
[0209] In some examples, the first wakeup signal resource
configuration indicates a number of different beams by which a
wakeup signal is transmitted within a transmission time interval,
and the wakeup signal transmission component 1520 may transmit the
wakeup signal transmission using the wakeup signal resource within
the transmission time interval based on the number of different
beams. Additionally or alternatively, the first wakeup signal
resource configuration may indicate a beam repetition factor for at
least one beam by which a wakeup signal is transmitted within a
transmission time interval, and the wakeup signal transmission
component 1520 may transmit the wakeup signal transmission using
the wakeup signal resource within the transmission time interval
based on the beam repetition factor.
[0210] In some examples, the first wakeup signal resource
configuration indicates a beam pattern for at least one beam by
which a wakeup signal is transmitted within a transmission time
interval, and the wakeup signal transmission component 1520 may
transmit the wakeup signal transmission using the wakeup signal
resource within the transmission time interval based on the beam
pattern. Additionally or alternatively, the first wakeup signal
resource configuration may indicate a beam pattern for a set of
different beams by which a wakeup signal is transmitted within a
transmission time interval, and the wakeup signal transmission
component 1520 may transmit the wakeup signal transmission using
the wakeup signal resource within the transmission time interval
based on the beam pattern.
[0211] In some cases, the decoding hypothesis component 1525 may
support each wakeup signal resource configuration of the set of
wakeup signal resource configurations corresponding to a different
decoding hypothesis of a set of decoding hypotheses. In some cases,
each decoding hypothesis of the set of decoding hypotheses
corresponds to a different beam pattern for at least one beam by
which a wakeup signal is transmitted within a transmission time
interval.
[0212] A base station 105 may implement the wakeup signaling
configuration module 1505. In some cases, the configuration
signaling component 1510 may configure a UE with a first search
space configuration for monitoring a downlink control channel while
operating in a low power mode and may configure the UE with a
second search space configuration for monitoring the downlink
control channel while operating in an active mode, where the second
search space configuration is different from the first search space
configuration. In some examples, the configuration signaling
component 1510 may transmit, to the UE, configuration signaling
configuring the UE with the first search space configuration, the
second search space configuration, or both. The wakeup signal
transmission component 1520 may transmit, to the UE, a wakeup
signal transmission using a wakeup signal resource according to the
first search space configuration based on the UE operating in the
low power mode.
[0213] FIG. 16 shows a diagram of a system 1600 including a device
1605 that supports wakeup signaling resource occasions in
accordance with aspects of the present disclosure. The device 1605
may be an example of or include the components of device 1305,
device 1405, or a base station 105 as described herein. The device
1605 may include components for bi-directional voice and data
communications including components for transmitting and receiving
communications, including a wakeup signaling configuration module
1610, a network communications manager 1615, a transceiver 1620, an
antenna 1625, memory 1630, a processor 1640, and an inter-station
communications manager 1645. These components may be in electronic
communication via one or more buses (e.g., bus 1650).
[0214] The wakeup signaling configuration module 1610 may transmit
configuration signaling configuring a UE 115 with a set of wakeup
signal resource configurations, transmit a configuration indicator
indicating a first wakeup signal resource configuration of the set
of wakeup signal resource configurations, and transmit a wakeup
signal transmission using a wakeup signal resource based on the
first wakeup signal resource configuration.
[0215] The network communications manager 1615 may manage
communications with the core network 130 (e.g., via one or more
wired backhaul links). For example, the network communications
manager 1615 may manage the transfer of data communications for
client devices, such as one or more UEs 115.
[0216] The transceiver 1620 may communicate bi-directionally, via
one or more antennas, wired, or wireless links as described above.
For example, the transceiver 1620 may represent a wireless
transceiver and may communicate bi-directionally with another
wireless transceiver. The transceiver 1620 may also include a modem
to modulate the packets and provide the modulated packets to the
antennas for transmission, and to demodulate packets received from
the antennas.
[0217] In some cases, the wireless device may include a single
antenna 1625. However, in some cases the device may have more than
one antenna 1625, which may be capable of concurrently transmitting
or receiving multiple wireless transmissions.
[0218] The memory 1630 may include RAM, ROM, or a combination
thereof. The memory 1630 may store computer-readable code 1635
including instructions that, when executed by a processor (e.g.,
the processor 1640) cause the device to perform various functions
described herein. In some cases, the memory 1630 may contain, among
other things, a BIOS which may control basic hardware or software
operation such as the interaction with peripheral components or
devices.
[0219] The processor 1640 may include an intelligent hardware
device (e.g., a general-purpose processor, a DSP, a CPU, a
microcontroller, an ASIC, an FPGA, a programmable logic device, a
discrete gate or transistor logic component, a discrete hardware
component, or any combination thereof). In some cases, the
processor 1640 may be configured to operate a memory array using a
memory controller. In some cases, a memory controller may be
integrated into processor 1640. The processor 1640 may be
configured to execute computer-readable instructions stored in a
memory (e.g., the memory 1630) to cause the device 1605 to perform
various functions (e.g., functions or tasks supporting wakeup
signaling resource occasions).
[0220] The inter-station communications manager 1645 may manage
communications with other base station 105 and may include a
controller or scheduler for controlling communications with UEs 115
in cooperation with other base stations 105. For example, the
inter-station communications manager 1645 may coordinate scheduling
for transmissions to UEs 115 for various interference mitigation
techniques such as beamforming or joint transmission. In some
examples, the inter-station communications manager 1645 may provide
an X2 interface within an LTE/LTE-A wireless communication network
technology to provide communication between base stations 105.
[0221] The code 1635 may include instructions to implement aspects
of the present disclosure, including instructions to support
wireless communications. The code 1635 may be stored in a
non-transitory computer-readable medium such as system memory or
other type of memory. In some cases, the code 1635 may not be
directly executable by the processor 1640 but may cause a computer
(e.g., when compiled and executed) to perform functions described
herein.
[0222] FIG. 17 shows a flowchart illustrating a method 1700 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The operations of method 1700
may be implemented by a UE 115 or its components as described
herein. For example, the operations of method 1700 may be performed
by a wakeup signaling configuration module as described with
reference to FIGS. 9 through 12. In some examples, a UE may execute
a set of instructions to control the functional elements of the UE
to perform the functions described below. Additionally or
alternatively, a UE may perform aspects of the functions described
below using special-purpose hardware.
[0223] At 1705, the UE may receive configuration signaling
configuring the UE with a set of wakeup signal resource
configurations. The operations of 1705 may be performed according
to the methods described herein. In some examples, aspects of the
operations of 1705 may be performed by a configuration signaling
component as described with reference to FIGS. 9 through 12.
[0224] At 1710, the UE may receive a configuration indicator
indicating a first wakeup signal resource configuration of the set
of wakeup signal resource configurations. The operations of 1710
may be performed according to the methods described herein. In some
examples, aspects of the operations of 1710 may be performed by a
configuration identifier as described with reference to FIGS. 9
through 12.
[0225] At 1715, the UE may monitor a wakeup signal resource for a
wakeup signal transmission based on the first wakeup signal
resource configuration. The operations of 1715 may be performed
according to the methods described herein. In some examples,
aspects of the operations of 1715 may be performed by a monitoring
component as described with reference to FIGS. 9 through 12.
[0226] FIG. 18 shows a flowchart illustrating a method 1800 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The operations of method 1800
may be implemented by a UE 115 or its components as described
herein. For example, the operations of method 1800 may be performed
by a wakeup signaling configuration module as described with
reference to FIGS. 9 through 12. In some examples, a UE may execute
a set of instructions to control the functional elements of the UE
to perform the functions described below. Additionally or
alternatively, a UE may perform aspects of the functions described
below using special-purpose hardware.
[0227] At 1805, the UE may receive a first search space
configuration for monitoring a downlink control channel while
operating in a low power mode of the UE. The operations of 1805 may
be performed according to the methods described herein. In some
examples, aspects of the operations of 1805 may be performed by a
configuration signaling component as described with reference to
FIGS. 9 through 12.
[0228] At 1810, the UE may receive a second search space
configuration for monitoring the downlink control channel while
operating in an active mode of the UE, where the second search
space configuration is different from the first search space
configuration. The operations of 1810 may be performed according to
the methods described herein. In some examples, aspects of the
operations of 1810 may be performed by a configuration signaling
component as described with reference to FIGS. 9 through 12.
[0229] At 1815, the UE may monitor the downlink control channel
according to the first search space configuration for a wakeup
signal transmission based on the UE operating in the low power
mode. The operations of 1815 may be performed according to the
methods described herein. In some examples, aspects of the
operations of 1815 may be performed by a monitoring component as
described with reference to FIGS. 9 through 12.
[0230] FIG. 19 shows a flowchart illustrating a method 1900 that
supports wakeup signaling resource occasions in accordance with
aspects of the present disclosure. The operations of method 1900
may be implemented by a base station 105 or its components as
described herein. For example, the operations of method 1900 may be
performed by a wakeup signaling configuration module as described
with reference to FIGS. 13 through 16. In some examples, a base
station may execute a set of instructions to control the functional
elements of the base station to perform the functions described
below. Additionally or alternatively, a base station may perform
aspects of the functions described below using special-purpose
hardware.
[0231] At 1905, the base station may configure a UE with a first
search space configuration for monitoring a downlink control
channel while operating in a low power mode. The operations of 1905
may be performed according to the methods described herein. In some
examples, aspects of the operations of 1905 may be performed by a
configuration signaling component as described with reference to
FIGS. 13 through 16.
[0232] At 1910, the base station may configure the UE with a second
search space configuration for monitoring the downlink control
channel while operating in an active mode, where the second search
space configuration is different from the first search space
configuration. The operations of 1910 may be performed according to
the methods described herein. In some examples, aspects of the
operations of 1910 may be performed by a configuration signaling
component as described with reference to FIGS. 13 through 16.
[0233] At 1915, the base station may transmit, to the UE, a wakeup
signal transmission using a wakeup signal resource according to the
first search space configuration based on the UE operating in the
low power mode. The operations of 1915 may be performed according
to the methods described herein. In some examples, aspects of the
operations of 1915 may be performed by a wakeup signal transmission
component as described with reference to FIGS. 13 through 16.
[0234] It should be noted that the methods described herein
describe possible implementations, and that the operations and the
steps may be rearranged or otherwise modified and that other
implementations are possible. Further, aspects from two or more of
the methods may be combined.
[0235] Techniques described herein may be used for various wireless
communications systems such as code division multiple access
(CDMA), time division multiple access (TDMA), frequency division
multiple access (FDMA), orthogonal frequency division multiple
access (OFDMA), single carrier frequency division multiple access
(SC-FDMA), and other systems. A CDMA system may implement a radio
technology such as CDMA2000, Universal Terrestrial Radio Access
(UTRA), etc. CDMA2000 covers IS-2000, IS-95, and IS-856 standards.
IS-2000 Releases may be commonly referred to as CDMA2000 1.times.,
1.times., etc. IS-856 (TIA-856) is commonly referred to as CDMA2000
1.times.EV-DO, High Rate Packet Data (HRPD), etc. UTRA includes
Wideband CDMA (WCDMA) and other variants of CDMA. A TDMA system may
implement a radio technology such as Global System for Mobile
Communications (GSM).
[0236] An OFDMA system may implement a radio technology such as
Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), Institute of
Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE
802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are
part of Universal Mobile Telecommunications System (UMTS). LTE,
LTE-A, and LTE-A Pro are releases of UMTS that use E-UTRA. UTRA,
E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR, and GSM are described in
documents from the organization named "3rd Generation Partnership
Project" (3GPP). CDMA2000 and UMB are described in documents from
an organization named "3rd Generation Partnership Project 2"
(3GPP2). The techniques described herein may be used for the
systems and radio technologies mentioned herein as well as other
systems and radio technologies. While aspects of an LTE, LTE-A,
LTE-A Pro, or NR system may be described for purposes of example,
and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of
the description, the techniques described herein are applicable
beyond LTE, LTE-A, LTE-A Pro, or NR applications.
[0237] A macro cell generally covers a relatively large geographic
area (e.g., several kilometers in radius) and may allow
unrestricted access by UEs 115 with service subscriptions with the
network provider. A small cell may be associated with a
lower-powered base station 105, as compared with a macro cell, and
a small cell may operate in the same or different (e.g., licensed,
unlicensed, etc.) frequency bands as macro cells. Small cells may
include pico cells, femto cells, and micro cells according to
various examples. A pico cell, for example, may cover a small
geographic area and may allow unrestricted access by UEs 115 with
service subscriptions with the network provider. A femto cell may
also cover a small geographic area (e.g., a home) and may provide
restricted access by UEs 115 having an association with the femto
cell (e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 for
users in the home, and the like). An eNB for a macro cell may be
referred to as a macro eNB. An eNB for a small cell may be referred
to as a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An
eNB may support one or multiple (e.g., two, three, four, and the
like) cells, and may also support communications using one or
multiple component carriers.
[0238] The wireless communications system 100 or systems described
herein may support synchronous or asynchronous operation. For
synchronous operation, the base stations 105 may have similar frame
timing, and transmissions from different base stations 105 may be
approximately aligned in time. For asynchronous operation, the base
stations 105 may have different frame timing, and transmissions
from different base stations 105 may not be aligned in time. The
techniques described herein may be used for either synchronous or
asynchronous operations.
[0239] Information and signals described herein may be represented
using any of a variety of different technologies and techniques.
For example, data, instructions, commands, information, signals,
bits, symbols, and chips that may be referenced throughout the
description may be represented by voltages, currents,
electromagnetic waves, magnetic fields or particles, optical fields
or particles, or any combination thereof.
[0240] The various illustrative blocks and modules described in
connection with the disclosure herein may be implemented or
performed with a general-purpose processor, a DSP, an ASIC, an FPGA
or other programmable logic device, discrete gate or transistor
logic, discrete hardware components, or any combination thereof
designed to perform the functions described herein. A
general-purpose processor may be a microprocessor, but in the
alternative, the processor may be any conventional processor,
controller, microcontroller, or state machine. A processor may also
be implemented as a combination of computing devices (e.g., a
combination of a DSP and a microprocessor, multiple
microprocessors, one or more microprocessors in conjunction with a
DSP core, or any other such configuration).
[0241] The functions described herein may be implemented in
hardware, software executed by a processor, firmware, or any
combination thereof. If implemented in software executed by a
processor, the functions may be stored on or transmitted over as
one or more instructions or code on a computer-readable medium.
Other examples and implementations are within the scope of the
disclosure and appended claims. For example, due to the nature of
software, functions described herein can be implemented using
software executed by a processor, hardware, firmware, hardwiring,
or combinations of any of these. Features implementing functions
may also be physically located at various positions, including
being distributed such that portions of functions are implemented
at different physical locations.
[0242] Computer-readable media includes both non-transitory
computer storage media and communication media including any medium
that facilitates transfer of a computer program from one place to
another. A non-transitory storage medium may be any available
medium that can be accessed by a general purpose or special purpose
computer. By way of example, and not limitation, non-transitory
computer-readable media may include RAM, ROM, electrically erasable
programmable read only memory (EEPROM), flash memory, compact disk
(CD) ROM or other optical disk storage, magnetic disk storage or
other magnetic storage devices, or any other non-transitory medium
that can be used to carry or store desired program code means in
the form of instructions or data structures and that can be
accessed by a general-purpose or special-purpose computer, or a
general-purpose or special-purpose processor. Also, any connection
is properly termed a computer-readable medium. For example, if the
software is transmitted from a website, server, or other remote
source using a coaxial cable, fiber optic cable, twisted pair,
digital subscriber line (DSL), or wireless technologies such as
infrared, radio, and microwave, then the coaxial cable, fiber optic
cable, twisted pair, DSL, or wireless technologies such as
infrared, radio, and microwave are included in the definition of
medium. Disk and disc, as used herein, include CD, laser disc,
optical disc, digital versatile disc (DVD), floppy disk and Blu-ray
disc where disks usually reproduce data magnetically, while discs
reproduce data optically with lasers. Combinations of the above are
also included within the scope of computer-readable media.
[0243] As used herein, including in the claims, "or" as used in a
list of items (e.g., a list of items prefaced by a phrase such as
"at least one of" or "one or more of") indicates an inclusive list
such that, for example, a list of at least one of A, B, or C means
A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also,
as used herein, the phrase "based on" shall not be construed as a
reference to a closed set of conditions. For example, an exemplary
step that is described as "based on condition A" may be based on
both a condition A and a condition B without departing from the
scope of the present disclosure. In other words, as used herein,
the phrase "based on" shall be construed in the same manner as the
phrase "based at least in part on."
[0244] In the appended figures, similar components or features may
have the same reference label. Further, various components of the
same type may be distinguished by following the reference label by
a dash and a second label that distinguishes among the similar
components. If just the first reference label is used in the
specification, the description is applicable to any one of the
similar components having the same first reference label
irrespective of the second reference label, or other subsequent
reference label.
[0245] The description set forth herein, in connection with the
appended drawings, describes example configurations and does not
represent all the examples that may be implemented or that are
within the scope of the claims. The term "exemplary" used herein
means "serving as an example, instance, or illustration," and not
"preferred" or "advantageous over other examples." The detailed
description includes specific details for the purpose of providing
an understanding of the described techniques. These techniques,
however, may be practiced without these specific details. In some
instances, well-known structures and devices are shown in block
diagram form in order to avoid obscuring the concepts of the
described examples.
[0246] The description herein is provided to enable a person
skilled in the art to make or use the disclosure. Various
modifications to the disclosure will be readily apparent to those
skilled in the art, and the generic principles defined herein may
be applied to other variations without departing from the scope of
the disclosure. Thus, the disclosure is not limited to the examples
and designs described herein, but is to be accorded the broadest
scope consistent with the principles and novel features disclosed
herein.
* * * * *